Xtremehorticulture

Buying New House May Need Lots of Plant Care

 Trees in the readers landscape Q. My wife and I just bought a house. The house has a backyard with a good selection of different fruit trees and non-fruit trees. We have noticed that as the trees were bearing fruit, the fruit looked a little spotted and not exactly healthy. The same thing was happening to the leaves, spotted & brown around edges. I thought it was due to lack of water? Then we started to notice that all most all the tree stumps had their bark opening in big patches and sort of peeling away. And now we see liquid, all most sap like coming from these areas. The Peach trees bark actually looks white on the outside! The trees don’t look healthy at all. It seems the trees were planted in 2004. A. After looking at all the trees sent to me in pictures, my first thought was that they could use 4 to 6 inches of wood mulch covering the soil beneath them.  You would see a big difference in their growth and health the season following an application.  Apple tree and trunk damage             You can pick up free wood mulch from the university orchard in North Las Vegas.  You just have to drive out there and get it. You can get directions by calling the master gardener helpline any Monday through Friday at 257-5555. The orchard is open for doing this on Tuesday and Saturday mornings.             All of the trees seem to have a lot of trunk damage probably due to borers.  I would to take a sterilized sharp knife and remove all of the loose bark and damaged parts of the trunk down to undamaged wood. At this point you will make your determination whether to keep them or start over. If the damage is over half way around the trunk, you might consider eventually replacing them. Less than that, it is probably worth trying to save them. Plum tree with trunk damage             If you decide a tree is worth keeping then trim the borer damaged areas, removing dead bark, all the way down to fresh, healthy tissue. It is okay to cut into this healthy tissue with a clean knife. It will heal over just fine as long as the trees get adequate fertilizer and water.             Next, paint the trunk and exposed limbs with diluted white latex paint to help prevent sunburn and lessen borer future borer damage. Dilute the white latex paint half and half with water.              Make sure the trees are getting adequate amounts of water on a regular basis. Right now, in late January, that should be once every ten days or thereabouts with about 15 to 20 gallons at each application. Got to once a week in February and twice a week in May. Peach tree with trunk damage             Fertilize each tree with a fertilizer that has all three numbers and no zeros. An example might be 10-20-10. You will probably not find this fertilizer exactly but the important part is that the middle number is highest. The easiest thing to do is to buy fertilizer stakes and pound them into the ground where the soil is wet after irrigating and at least 12 inches away from the trunk.             At the same time apply an iron fertilizer to the soil, specifically iron EDDHA chelate. All in all they look remarkably healthy except for the insect damage. Make sure you get wood mulch and apply fertilizers to the trees again next January.

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Bigger Black Mission Figs With More Water

Black Mission figs at The Orchard  This is what I have been telling you guys. This is taken from the publication, California Agriculture, published back in 1999 by David Goldhamer and Mario Salinas from the University of California Cooperative Extension and the Ag Research Center in Parlier. The research was focused on the San Jaoquin Valley in California. An analysis of tree-water relations and fruit yield indicates that Black Mission fig production responds favorably to a higher volume of water applied during the summer than is currently used by most of the industry. Larger fruit size was the primary yield component responsible for the improved production and profit. Based on historical reference crop evapotranspiration rates and the crop coefficients determined using data from this study, summer applied water should be about 36 inches for maximum Black Mission fruit production and grower profit in the Madera area. Bottom line. If you are unhappy with the size of your figs or fig production, make sure your fig trees are not water stressed when they are producing figs.  Use surface mulches to conserve water, keep the soil from wild fluctuations in water content that will affect fruiting and the mulch helps keep fallen fruit from rotting on the ground. Open publication – Free publishing – More fig production

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Directions for Planting a Bareroot Fruit Tree

Planting a Bareroot Fruit Tree Materials Needed: ·         Shovel ·         Predug hole three to four feet in diameter ·         Three to four cubic feet of compost per tree ·         Preplant fertilizer (triple super phosphate or high in phosphorus) ·         Wooden or metal stake at least four feet long ·         Hammer ·         Green nursery tape ·         Whitewash or white latex paint diluted equally with water ·         Paint brush ·         One 24 inch X 3’ section of one-inch hexagonal chicken fencing (if rabbits a problem) ·         Wood mulch ·         Bypass type hand pruner Planting hole for fruit trees with amended soil 1.    Dig hole 4 feet in diameter and the depth of the root system. It normally does not have to be dug any deeper than this. 2.    Reserve soil from the hole for mixing with compost called backfill 3.    Remove rocks larger than a golf ball. 4.    Add compost to the backfill and mix thoroughly. 5.    Add preplant fertilizer to the compost soil mix and thoroughly mix. 6.    Place tree in the planting hole and orient the bud union (dogleg) to the north. And make sure the roots will be ½ inch below the finished soil level when finished. 7.    Put three to four inches of amended soil into the bottom of the hole and start adding water. The water should turn the soil into a slurry (consistency of a milk shake) and flow around the roots, removing air pockets. 8.    Continue to add the soil/compost/fertilizer mix to the planting hole as water is added. 9.    When the backfill has been added completely, collapse the edges of the planting hole with your shovel to create an irrigation basin for watering. This basin should be level and have a depth of three to four inches. If a basin does not exist, create one by piling soil around the edge of the planting hole to create a moat. 10. Once the tree has been planted and the water has drained, check to make sure no roots are exposed. Draining may take anywhere from minutes in well drained soils to hours in poorly drained soils. If the roots are exposed, cover the roots with amended soil but be careful to leave a three to four inch deep, level basin (moat) surrounding the tree and encircling the planting hole. Fruit tree watered in but missing the stake to hold the roots from moving 11. Drive a four foot or longer stake with a hammer into the hole directly next to the tree. Make sure the stake is solidly driven into the soil at the bottom of the hole. The stake should be immobile after it is driven into the bottom of the hole. 12. Using green, pliable nursery tape, tie the tree tightly to the stake so that the tree is immobilized. When planting bareroot trees, the tree must be immobilized in its first few months during establishment in its new home. This allows for strong, healthy and fast root development by mid to late summer. The stake should be removed the following spring. 13. If the tree has not been whitewashed, then whitewash the tree using either whitewash compounds or diluted white latex paint (half water/half white latex paint). Paint the trunk, trunk bud union and any major stems coming from the trunk to a distance of two inches from the trunk. 14. Spread the wood mulch throughout the basin to a minimum of three inches. Pull the mulch away from the trunk of the tree six inches to allow for drying of the trunk between irrigations and avoid crown rot. 15. If you live near the desert, golf course or park protect your new investment with rabbit fencing.  Encircle the tee with 24 inch (wide) X 3 ft (long), one inch mesh, chicken wire. Tie the ends of the fencing together so that rabbits cannot get inside and damage the tree. Bury the bottom edge of the fencing two inches into the mulch. 16. If your tree does not have any limbs low to the ground, prune the main stem of the tree at knee height if you want your fruit production as low on the tree as possible. This will force the tree to produce branches and fruit lower to the ground for easier picking later in its life. 17. Irrigate the tree daily for the first three days to continue to remove air pockets. Wet the soil surrounding the hole and settle the plant into its new home.

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Olive Trees With Mossy-Like Growth On the Branches

Olives with mossy growth inside Q. I am a master gardener in Lake Havasu City, AZ. I am attaching photos of an olive tree at LH Baptist church. There are 4 trees and have been planted at least 40 years ago from what anyone can remember and they have “always” been trimmed into little balls. They are being watered for about 10 minutes every day in the summer and about 10 minutes twice a week in the winter. As you can see in the last picture, they do not have wells but have a raised brick planter box. It’s hard to tell but the tree is about 1 1/2 feet deep in this planter. Two of the trees are o.k. There are many basic problems with the care; however, my main question is that 2 trees appear to have some type of mossy growth inside on the branches. It shows up best on the last picture. Can you help identify this and give any advise for care. Olive mossy growth on the inside A. I am going to have to do some guessing on this one. This is not something that comes to mind easily. First of all telling me that they are watered in minutes doesn’t give me any idea of how much water they are getting. If  this is ten minutes on a traditional bubbler irrigation system then this could be between 10 and 20 gallons per day depending on whether these bubblers are one or two gallon per minute bubblers. If this is drip irrigation it could be anywhere from a liter of water to a couple gallons depending on the type of emitter, how many there are and how fast they release water. Let’s just assume I guess that they are not getting enough water. Olives are traditionally grown in Mediterranean climates; hot dry summers and cold wet winters. Olive trees are very drought tolerant but if they are being grown for their fruit then they must have adequate water during times of fruit production. Adequate water for trees is watering them deeply but infrequently. Deeply has to do with the quantity of water applied at the time of irrigation. Deeply means the water should be applied in a large enough quantity to water to a depth of about two feet deep in the soil surrounding the roots. If the water is not a good quality water, such as saline or water containing significant levels of salt, then it must be watered even more deeply to keep salts flushed from the roots. Olive flower racemes Infrequently means how often the water is applied. In your case, the trees are watered too often but MOST LIKELY not enough water is applied at each irrigation. So increase the volume of water applied  AND have the water come on less often. Now the mossy growth. This is where I am taking a bit of a shot in the dark. If these olives were planted 40 years ago they were olives that produced fruit. Fruitless olives were not being marketed then. There is no mention of fruit production. Olive flowers come out on clusters called racemes which also bear the fruit. If there is inadequate water (drought stress) the tree will have a rough time keeping these flowers and racemes alive and probably produce little to no fruit. My guess is that these are dried up flower clusters (racemes) that never were sustained for producing fruit either by a lack of pollination or enough water to keep the raceme alive and so the raceme dried up giving you the “mossy growth” you are referring to. But this is just an educated guess.

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How to Prune Texas Rangers

  Q. Last year I read in your blog how to prune texas rangers.  Now I can’t find that article.  Can you repeat it?  Thank you. A. Maybe this is it. Q. I would like to cut back some cassia, Texas ranger and rosemary plants that has grown too large. When is the best time to do so? A. There are three cassias that are commonly planted here; feathery cassia, silverleaf cassia and desert cassia. They either bloom in the spring or spring and fall. This means the flowers have to be formed on last year’s wood if they bloom in the spring.             Basic rule of thumb is that plants that are not appreciated for their flowers then prune them back during the winter months after leaf drop. However, if it is very light pruning then you can do that any time. Texas ranger sheared so flowers are removed             On those plants which are grown for their flowers then prune them as soon as their bloom time is over regardless of the time of year. If plants bloom in the spring then prune them as soon as they are done pruning in the spring. This will give them time to initiate flower buds during the late summer for next spring’s bloom.             If they bloom in the summer months, then they put flowers on spring growth. If you prune these in the spring you run the chance of pruning off all the flowers if they are not pruned correctly. This is very often done to oleanders when they are hedge sheared during the spring or early summer months. What it will look like if it is not sheared So with this in mind…. Removing wood from Texas ranger now also removes flowers so do not prune with a hedge shears or you will remove the flowers as well. Make your cuts deep inside the canopy, removing larger stems at a crotch and remove an entire stem when you do. Do not cut it just halfway back. Leave the newest growth on the remaining stems to bloom for you. By opening the canopy for light you will see new sprouts being produced deeper inside. These newer sprouts will produce wood for flowers later in the year and over the next couple of years if you do not cut off the growing tips.  Next year, remove more older wood from deep inside the canopy and repeat this each year “renewing” older wood and reinvigorating flowering. I hope this helps. I attached two pictures of texas rangers taken in april. One was hedge pruned. The other not. One is blooming. The hedge pruned one had all the growth cut off that would have produced flowers.

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Science in Action: Las Vegas – Making the Desert Bloom

            Question. Where can you go and visit Egypt, Sherwood Forest, New York, a tropical island, a Pirate’s island, Monte Carlo, the Italian Riviera, jet skiing on a large lake or snow-skiing on a nearby, 14,000 foot mountain all in a day? Las Vegas now boasts the eighth busiest airport in the United States and the tenth in the world. When you count tourists and convention delegates at 32 million each year, their isn’t any city busier. The closest comparison would be the crowds visiting the Orlando area attractions, the busiest multi-city area in the US. So what’s the problem? It isn’t what you think. Yes, Las Vegas receives less than 4 inches of rain each year. Yes, the summertime temperatures soar above 110 for long periods of time in the summer. Yes, the humidity is usually below 10 percent and the wind speed is usually among the highest in the Southwest. But many places  in the desert Southwest are like that. Corrosion to sidewalk from salts             It is the soil. The soils in Las Vegas are among the worst of any major city in the world. Native desert soils have salt levels 25 times higher than most Extension Services would consider safe. Boron levels, where one ppm can be considered lethal for many plants, can exceed 40 ppm in isolated pockets designated for development. With pH levels often over 8.5, sodium  and caliche change the soils so much that they require picks or jack hammers for planting. Las Vegas soils are frequently very high in gypsum. The gypsum levels are so high that there are two gypsum wall board plants in the area. The sulfates contained in gypsum can be extremely damaging to unprotected steel and concrete. Water has been cheap in Las Vegas in the past. This, combined with the efforts to promote tourism and gaming here, has created an artificial, desert rainforest in the urban areas. The highly soluble gypsum has dissolved in these irrigated desert soils, leaving voids that are filled by collapsing soils that damage walls, foundations, roads and structures. The Colorado River water used for irrigating in Las Vegas contains one ton of salts per acre foot. What does that mean to residents? A normal lawn irrigated in Las Vegas will receive about 600 pounds of salt each year. Salt damage to block walls due to salt in soil and water             Even with its problems, the gardening season in Las Vegas extends through most of the year. The heaviest planting season is in the spring but fall planting is a regular and growing practice with Las Vegas residents. Most major nurseries like the string of Star and Plant World nurseries operate throughout the year with some seasonal sales during the slow months at Christmas. There are essentially no wholesale growers in southern Nevada. In fact, there has never been an attempt at wholesale growing since the population and growth spurt after 1984. Currently, Las Vegas is a retail market in nursery goods with wholesalers from the surrounding states. Major plant sales are through direct sales or plant brokers. The use of color in business complexes, hotels and wholesaling to mass merchandisers like Wal-Mart, Kmart, Target, Home Depot and Builder’s Square and nurseries is big in Las Vegas with the dollars all going out-of-state. Yet publications and syndicated talk shows claim that Nevada is the number one state in which to establish a new business. Las Vegas Valley Water District Desert Landscape Award Winner             Las Vegas is a service-oriented town. The 4 – 6,000 people who moved to the area each month until a few years ago come here with the expectations of a 24 hour town and having a good time. Many want the freedom that service companies provide to avoid the heat and have the time to enjoy a 24 hour town. Rough estimates of the percentage of residents using lawn maintenance companies would put it at about 10 percent. The traditional grass/tree/shrub landscapes are becoming a thing of the past because of increasing water costs and environmental awareness. Because of a heightened awareness in conserving water and sensitivity to the desert environment, there has been a growing trend toward a dry-type of landscaping. Desert-adapted plants and examples of the Sonoran desert landscape “feel” have been becoming more attractive to new residents. This has presented installation and maintenance problems to old time landscapers who “grew up” with the old Las Vegas mentality of “keep it green” and “green side up”.             The megaresort gardeners are faced with a huge problem the moment a landscape architect from outside the area draws up plans for a new hotel.  Under the demands of the owners, the new property must be different than anything else already here and give an appearance that the customer is not in a desert. Seventy-two and 90 inch boxed trees like English oak are brought in from the east coast on flat beds in the middle of summer to a meet a deadline for “Sherwood Forest”. Pine needles are brought in by the boxcar load on a train to simulate a Carolina landscape. Eighty acres of sod are trucked in from out of state on a revolving caravan of flatbeds to meet a deadline for a recreation facility. A few years ago the whole idea would have been preposterous. Now it’s being done. TPC one of the desert southwest courses             Horticulture in Las Vegas is big business. And like the craps tables, it can be in one big throw. Approximately 5 percent of a hotel’s construction and material costs are in landscaping. This doesn’t take a genius to figure out that a billion dollar megaresort owns a good-sized nursery when it’s completed.  A few years ago the gardening done in the hotels were done by a small union crew out of the Engineering department. The whole operation would be overseen by the Director of Operations. Because of the high degree of technology now involved in gardening at

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Considerations for Desert Landscape Designs

            One of the fears about landscapes designed for desert environments is that the design will actually use more water than was anticipated. In the process of using more water than anticipated and lack of attention to design considerations, the energy consumption of the building or home might increase. Minioasis concept taken from Sunset Magazine many years ago. Hope you guys don’t mind.             Landscape designs are extensions of the home and should provide usable areas that add to our quality of life. Recently a homeowner asked how to know if a landscape designer was a good one or not. A good designer will sit down and ask you what your needs are as a family or a business. A good designer will incorporate as many of these needs as possible into the design.. If the designer doesn’t ask about your needs, get a different designer.             Concentrate most the plants near the home and decrease plant density away from the home or building. Common terms used to describe this are minioasis and hydrozoning designs. This technique allows you to use high water use plants near the foundation where shading of the windows and walls can occur. In Las Vegas, where we have some gypsiferous soils in parts of the valley, this can present a problem if these “foundation plants” are overwatered. The high sulfates contained in some of our soils may damage concrete patios and foundations. Check with a soil survey map or have the soil analyzed for high sulfates. The only solution to this type of problem is to keep foundation plantings on drip emitters and far enough from concrete so that the water/soil solution can’t react with the concrete. Most cement companies use appropriate, resistant cement in their batches.             Shade south and west facing walls. Some research in the past few years has indicated that shading the south and west facing walls, not the roofs, helps to reduce energy consumption of buildings situated in desert landscapes. This can be accomplished with trellised vines, shrubs or well-placed trees. Using large trees in desert landscapes to shade is questionable due to water use             Use trees that are in scale with the building. Large trees use more water than smaller trees. Even if a large tree is a so-called low water use tree, a smaller tree that might not be as water efficient may save water in a mature landscape. Water use rises dramatically with tree canopy volume. It makes no sense at all to plant a 40 foot tree to shade a one story building in our desert environment. Our main problem is to find good, small trees for small residential landscapes. More attention needs to be paid by our nurseries to developing some of our reliable large shrubs as small, specimen trees. Ikebana floral designs use spaces creatively             Use open spaces creatively. You’ll never save water by covering the soil with a plant canopy. The desert doesn’t do it and neither should we. Instead it is the challenge of a good designer to find creative ways to use open space. In Las Vegas of the past, if the designer had bare ground, they covered it with turfgrass. That time is gone and most people now realize that 100 percent turfgrass cover is irresponsible in our desert climate. Use turfgrass as a functional landscape planting, not a groundcover. It may be used to surround trees and shrubs that don’t do well under drip irrigation.             The temptation might be to replace turfgrass with a green, desert groundcover like myoporum. That would be a mistake. Recent research in Las Vegas has demonstrated that myoporum uses over thirty percent more water than high maintenance bermudagrass. Play it safe. Be creative. Open spaces don’t use water.             Consider hardscapes (boulders, covered patios, artwork, bridges, masonry, gazebos, fences, archways, benches) as alternatives to unnecessary plants in the design. Hardscapes don’t use water. Can a piece of hardscape be used to create shade instead of a large tree? Can it act as a focal point? Save plants for important items in a landscape and make them count. Plant use should be questioned if they are acting as a landscape filler.             Incorporate elevation changes in the design to create interest, create areas in the landscape to collect water and protect sensitive plants. Elevation changes provide niches for plants that might not survive normally.             When landscaping or relandscaping, a conscious effort should be made to follow the lead that deserts provide for us. Observe their characteristics and mimic them in the landscape. The house or building is situated in a “minioasis” in the desert landscape where it is protected from the harsh elements. Here it offers a retreat providing recreation, safety and comfort for the desert dweller. Checklist: What Should I Consider in a Design That Will Add to the Quality of Life in a Desert? How can I channel available breezes into living areas What are my solar angles and where is the sun shining from during the summer How can I control prevailing winds that are a nuisance Will there be glare into windows from my design Can I do anything to reduce dust problems inside the home Where do I need focal points and splashes of color How can I create interest with bare ground or “negative space” What kind of microclimates am I creating with my design What kind of spaces am I defining with my design and are they functional Am I creating areas of recreation and areas for leisure activities Am I creating shady spots for play areas, parking, patio, deck Am I shading the windows Am I considering attracting wildlife through the design Am I avoiding allergy plants Am I creating a safe design sensitive to the family’s needs and concerns Am I addressing their privacy concerns Am I stimulating all the human senses, not just sight

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I Want Quince Trees But Can’t Find Them at the Nursery

Quince fruit tree at The Orchard Q. My family has for many years had access to wild abandoned Quince bushes “trees”. They apparently were part of an old homestead in our native Orinda, east S.F. bay area. We have since moved from there, and see that you list this fruit as a tree that may survive here in the Vegas area with the proper soil. We have not been able to find the fruit available anywhere, it seems to be one of the forgotten. Apparently it is popular in the mediterranian to some degree. Any help finding a source to pick or buy would be greatly appreciated. There are seeds available though, and growing our own is looking like our only option. My mother lives here in Vegas, I am her son and now reside in Humboldt county “Willow Creek”. Quince fruit A. I have brought quince into the valley from Dave Wilson nursery and they are hard to sell. Not many people know about them and even fewer know what to do with them. I see that Bay Laurel nursery, an online nursery, carries quince; all three commonly recommended, orange, pineapple and Smyrna. Any will grow here in las vegas with few problems except iron cholorsis (leaf yellowing with green veins you use chelated iron in the soil in January EDDHA type or 138 Fe) and borer problems so whitewash them. Quince is popular in Mediterranean and some Arabic/Persian cultures where it is used in cooking a lot. Makes some great candies, infuses wonderful aromas into foods and makes great jams, jellies and compotes. Yes, improve the soil at planting time with composted manure and use organic surface mulch as I recommend and it performs well here with high quality fruit. http://www.baylaurelnursery.com/quince.html

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Oleander Has Leaves That are Crunching Up

Q. I have 4 oleander bushes that were doing great, now 2 of them are drying up the leaves are turning light and they are crunching up, what is going on. The ground seems wet enough, what is happening. I need your help are the dying? Freeze damage and spring recovery oleander A. The information I think I have from you is that you have four oleander bushes that have done well for several years and now some of them are drying up after a previous several year history of doing very well. The number one problem is a lack of water. I usually try to focus on the easiest possible reasons first because they are the most common. I realize your reaction will be to say it is not that but please check to make sure the water source has not been blocked, if this is drip irrigation, or reduced dramatically. I would assume that they are on the same valve so they are getting water at the same time off of the same irrigation valve. Also please realize that if the water was turned off for a long time, and then turned on again, that the soil can be moist but moistened after the damage was done. Not oleander but pittosporum with drought stress There is a lag time between damage to the plant where you will see the damage (leaves are dry and crunchy) and when the damage occurred. This could be a week or more. Visual appearance of drought damage lags behind the actual time the damage occurs. If it was drought damage, they will recover if water is reapplied and it is done before too long of a time (if the water is turned off for months when it is hot the plants will most likely not recover). The type of oleander may also dictate damage like this. For instance the petite oleanders, with the salmon colored flowers, are damaged with light freezes. The standard oleanders (large shrubs whites, reds, purples, etc.) are more cold hardly. However, there are differences in cold hardiness (dieback to or near the ground) between even the standard varieties but many of these die back ranging in temperatures dropping below 20F and down to about 10F. A few diseases but not much. There is one oleander disease that has, to my knowledge, been found in southern Nevada that causes leaves to scorch… appropriately called oleander leaf scorch disease. It has been found in southern California and Arizona. Here is a link to some information on the disease but it usually does not cause the entire plant to die since you can cut it to the ground and it will regrow with uninfected plant parts. http://ag.arizona.edu/plp/plpext/diseases/trees/oleander/oleleaf.htm Other rare disease problems include sooty canker and root rots but this would be highly unlikely from your descriptions AND they typically do not cause total plant death. Because oleander has so few problems in our climate we start getting into some weird and highly unlikely possibilities which center mostly on the soil and what may or may not have been put on the soil close to the plant. So then you have to go back into the history of how the plants were managed. Was there anything applied to the soil near them? Fertilizer applied right next to plants can cause scorching and even plant death. If it persists, replace the plants and the soil in those spots if the irrigation checks out okay.

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Science in Action: Hydraulic Lift Little Understood in Plants

Deep tree roots are important for large trees. We know that these roots help to stabilize large trees, keeping them anchored during high winds, and we know that it is important to get deep rooting established in landscape trees when transplanted into urban residential environments. Early research at the University of Arizona traced deep roots of native mesquite to depths below 200 feet. More recent research suggests that these deep roots are important for other reasons. Sinker roots of mesquite not irrigated but close to a river             Global research which surveyed maximum rooting depth of plants (trees, shrubs, perennial grasses) in natural settings (290 observations, 253 species) found a range in average maximum rooting depths from one foot (plants growing in northern tundra regions) to over 200 feet in deserts like the Kalahari; 194 species had roots at least six feet deep, 50 species had roots fifteen feet or more and 22 species had roots more than 30 feet deep. When the researchers grouped these plants by similar natural habitats, they found the average maximum rooting depth to be 6 feet for cropland, 30 feet for deserts, 12 feet for conifer forests, and nine feet for deciduous forests. When plants were again regrouped into three groups based upon growth habit, then trees had an average maximum depth of 20 feet, shrubs 15 feet and herbaceous plants (nonwoody) 7.5 feet. This research showed that deep rooting is quite common in woody and herbaceous species in natural habitats, far deeper than the traditional view held up until now.             Deep rooting is suspected, and research supports it, to be more important than just structurally anchoring plants in the landscape. Research supports that they could be very important for moving and releasing nutrients and water, both up and down, and redistributing water and nutrients among different soil profiles. Water movement up roots into drier surface soils may affect water use estimates trees and other plants growing in their vicinity.             Many woody plants utilize deep roots for water uptake, particularly when surface soils are dry, but how they do this is not well understood. It was thought to be a combination of water “pulled” up through the tree by evapotranspiration and capillary action (like a soda straw) and little understood process called “root pressure” (like a submersible pump). Measuring water moved from deep in the soil by roots has always been difficult without disturbing the roots and accessing these roots. Roots of irrigated fruit tree pulled from orchard             However a plant process for moving water deep in the soil profile to upper soil profiles through plant roots has been identified more recently. Research found that during periods without rain, upward flow through deep roots was continuous during both day and night using a plant process researchers call hydraulic lift. Researchers identified that this process contributed up to 20% of daily water movement from that depth with no evidence of nighttime transpiration and no water storage inside the plant. Research done in Texas on tree roots of two native trees found that roots growing at 20 to 60 feet below the soil surface contributed 20 – 50% of daily transpiration, depending on the water content of surface soils. As surface soils dried, more water was taken from deeper sources. All of this water from deeps soils was attributed to the plant’s hydraulic lift. Large quantities of this water are lifted at night. When hydraulic lift occurs at night then it is termed nocturnal hydraulic lift.             The question then becomes, if available water is moved from deep sources through deep roots during nighttime, when the plant is not transpiring for transpiration the next day, then where is this water stored? Other research indicates that water lifted from the deep soil profile is redistributed to dry, shallower soils where it is stored and used in the future. Deep root water transport varies with changes in the environment. When shallow soils become wetted again due to rain and/or the plant’s need for water decreases, hydraulic lift stops or is reduced dramatically. Hydraulic lift is the passive movement of water from roots where water is more available to roots or root compartments where the soil is drier. It does not require plant energy. While the majority of documented cases for hydraulic lift are in native plants in desert or arid climates, recent studies (such as those in the Northeast with Sugar Maple) indicate that hydraulic lift is not restricted to desert or arid species or regions. Release of water into the upper soil layers has been shown to benefit plants neighboring roots responsible for hydraulic lift. Because soils tend to dry from upper soil profiles downward and nutrients are usually more plentiful in the upper soil layers, lifted water may provide moisture to dry surface soils and enhance mineral uptake, beneficial microorganism growth such as mycorrhizae, and uptake of nutrients by feeder roots which typically occupy shallow soils. Some researchers feel that this is a form of plant parasitism and may have been the primary selective force in the evolution of this process. Hydraulic lift may also prolong or enhance root hair activity by keeping them hydrated. The direction of water movement in deep roots may be upward, downward or horizontal depending on where soil moisture is more limiting. The transfer of water downwards by root systems, from lets say roots growing in wet shallow soils to dry deep soils, has been termed downward siphoning or inverse hydraulic lift; the reverse of hydraulic lift. Such downward movement through the root system may allow growth of roots in otherwise dry soil at greater depths, permitting more rapid establishment of some plants. The amounts of water stored deep in the soil are not likely to be significant contributions if plant drought is severe. However, downward transfer of water may be important to plant establishment and the reduction of waterlogging in certain soil types. Inverse hydraulic lift may facilitate root growth into deep soil layers and transfer

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