xtremehorticulture – Page 290 – Xtremehorticulture

The Problem With Pruning Pine Trees So They Don’t Blow Over

5 Comments / blowover, limbs breaking, pine trees, pruning, wind / xtremehorticulture

A fairly recent trend in pruning in Las Vegas has been pruning pine trees so they don’t blow over. We have some wind gusts that periodically get pretty nasty when they reach speeds of up around 70 mph (112 kph) or more. The trend was to remove some of the canopy so that there is not so much leverage on the root systems. This leverage, or sail effect, by the wind can pop the trees over when gusts come up quickly and our trees can be pretty shallow rooted which does not help to anchor them. This Mondale pine was pruned probably in an attempt o reduce with wind load (sail effect) on its canopyand help reduce the potential for blowing over You can see that removing the inner small branches concentrates the weight of the new growth all on the ends of the branches causing them to bend and in some cases to break I have some concerns about thinning pine trees to allow more wind to blow through their canopies. Not that it is done but really more about HOW it is done. Take a look at this picture of a pruned pine tree just for that purpose. Most pine trees will not regenerate new growth on older branches once this growth is removed. Once the wood is older than about three years old most pines will not cause new growth to come from this older wood. Once this young wood is totally removed, it is gone for good. By removing these small limbs in the interior it prevents pines like Mondale from renewing the removed growth. The juvenile part of the limb is now concentrated only in the growing tips which are all at the ends of the branches. This might be good in theory (the tree trimmers don’t have to come back as often). But this can create a problem.Think of a fishing pole. Why is the pole diameter tapered and not all the same diameter along its length? Poles or branches which are tapered help spread the stresses of bending along its length. If a pole or branch has no taper, then the stress of bending is concentrated in a very small area of the pole or branch which will increase its chances of snapping or breaking. By removing this small wood deep on the inside it also causes these “thinned” older limbs to no longer increase in girth (caliper or diameter).They bend more and more as the weight of the new growth is added to the ends of the branches. Pine tree with a canopy thinned a bit better so that limbs are less likely to bend and split A better approach would be to selectively leave some juvenile wood on the interior of these larger diameter branches so that these branches will increase in caliper and taper. So instead of removing ALL the small juvenile from branches deep in the inside, remove some but leave some as well. This still results in thinning and allows for wind to move throught the canopy easier and also results in distributing this increased load along the branches rather than concentrating the load in a small area of the branch which increases its likelihood of failure (snapping or bending). Just a thought.

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Sap Oozing from Plum Tree Trunk

Leave a Comment / bubbles, hard, santa rose plum / xtremehorticulture

Sap oozing from the trunk of plum Q. Last week I noticed sap bubbles 6 to 8 inches off the ground on the trunk of my year old Santa Rosa plum. I removed the bubbles and reapplied the whitewash. I checked again today and they are back. I’ve had plums before and the boars always win. I had hoped the Santa Rosa would do better. What can I do to save this tree? A. Bubbles on plum don’t necessarily mean borers. They can do this with high temperatures. If you don’t see any other evidence of borers like bark coming off especially on the south or west sides then I would leave it alone. Repainting is fine. Try to keep as much shade on the trunk as you can from the canopy or even lean a board on that side of the trunk to shade it if you care to. If there is chicken wire around it for rabbit protection you could wrap something around the chicken wire for some shad on the trunk. I don’t know of any difference between plums in borer resistance so I don’t think that would make any difference. But for now just get some shade on it.

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Roses in the Hot Desert Do Well But Different From Growing in New Jersey

Leave a Comment / dying, iron chelate, Las Vegas, rock mulch / xtremehorticulture

Garden rose not doing well in our desert soils. They can do VERY well if you just follow some simple advice Q. This past spring I cleared a large “L” shaped area in my yard and planted 8 various rosebushes. They have sun from about 9 a.m. to about 5 p.m. They are watered in the evening and fed regularly. They are well planted with planting medium in large holes, and then mulched. All flowered during the spring and early summer. Now, however, they are very spindly looking. The leaves left on them are brown and the stems are turning brown. There are no bugs that I can see. I tugged on them and they are still firm in the ground. Have they died and should I replace them, or wait until spring and see what comes back? Should I cut them back, and if so, how much? I do not want to cut too much off. Leaf scorch on rose due to lack of soil improvement, no organic mulches used and not using an iron chelate as part of your fertilizer program A. Roses will grow best in an eastern exposure with protection from late afternoon sun. They can grow in full sun but they will be best grown in the exposure I mentioned. It is important to use a good compost mixed in the planting soil at the time of planting as well as a starter fertilizer high in phosphorus. Make sure your plants were planted the same depth as in the container or in the nursery if bare root. Make sure the bud union or dog leg on the stem is above ground and not buried. Make sure you stake the rose bush at the time of planting. The stake should not move if you do it correctly. I use a two foot piece of 3/8 inch rebar and tie the rose stem tightly to the rebar with green nursery tape and remove it after one growing season. Roses do well on drip irrigation. Use two emitters per plant or you can use drip pipe with inline emitters such as Netafim, Geoflow or equivalent product. If on drip it is important to note the amount of water the emitters deliver per hour and adjust your time on the emitters so that each plant gets about two to three gallons every time they are irrigated. Irrigations should be about two to possibly three times per week this time of year. Less often as it gets cooler but the length of time or hours should remain the same. Roses doing quite well in our hot desert climate and poor soils It is best to use a wood mulch rather than a rock mulch. All mulches must be pulled away from the rose stems at least 6 inches at the time of planting or the roses can get crown rot on the stem and die. Fertilize roses once in January with a rose fertilizer plus a soil applied iron chelate containing EDDHA. Follow label directions. You can fertilize again lightly after the heat of the summer has passed to help stimulate fall rose production. This should get you going. My guess is that they may have been planted too deep or the mulch touching the rose stems may have caused collar rot or irrigations may have been inadequate; either too often or not enough water. Just a hunch.

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Palo Verde Dont Like Butch Hair Cuts

Leave a Comment / pruning, sunscald / xtremehorticulture

Q. Attached are pics of a Palo Verde which has some unusual black growths on the upper sides of the limbs. I’m wondering if it has something to do with pruning, since it appears to be only in areas that have been pruned, although other pruned areas are unaffected. Damage to upper surface of palo verde limbs from reader Palo verde pruned too high, in my opinio, allowing for potential sunburn on upper surface of limbs Palo verde with sunburn damage, borer damage and limb and trunk damage A. My first reaction to the pictures was sunburn damage. But I would have to see if this damage was sunken like a canker. Next I would take a sterilized knife and cut around the edge of the damage and through the damage to see if the wood below the damage was dead or not. If it was dead below the damage and the damage was sunken then it is most likely sunburn damage to the limbs. The pics you sent had damage all on the upper side of the limbs which is consistent with sunburn damage. You wondered if it might be associated with pruning which it is. The big mistake people make on Palo Verde with the photosynthetic green bark like is pruning so much that too much light gets inside the canopy and burns these photosynthetic limbs. Even though the are designed to absorb light there is such a thing as too much light. These trees don’t make a lot of shade and when we remove too much canopy we will get sunburn on the limbs. Once we get these limbs sunburned then we have to look for possible borer damage. They go hand in hand and several borers are general feeders and are not really particular what they lay their eggs on. The adults focus on damaged trees for egg laying. So cut into the damage and look for football shaped exit holes about 3/8 to ½ inch long and ¼ inch wide under the damaged, sunburned bark. If this is the case, don’t prune so heavily next time and leave enough cover to prevent sunburn.

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Leave a Comment / desert landscape, ornamental plum, pink leaf color / xtremehorticulture

Ornamental or flowering plum leaves with wind damage Q. I put in a desert landscape with 2″ of rock in the front yard with various bushes and 2 flowering plum trees. This probably was a mistake, as I read one of your articles which said that this type of tree is not suited for rock mulch. Anyway, my question is about watering the trees. I have a 28″ diameter by 5″ deep watering reservoir around each tree. There is a layer of bark mulch in the reservoir. Right now I water the trees twice a week filling the reservoir up twice at each watering. This is purple leaf plum in a desert or rock landscape. It will look good for about five years without much attention. But after about five years it usually starts with leaf scorch and may begin getting iron chlorosis So far every summer around August some of the leaves partially dry out and turn brown. Is this caused by too much water or not enough? I water the bushes 3 times a week by drip system for 30 min per watering. They are all healthy and green. Also the bark on the trees are splitting in places and falling off. Do you think I will loose the trees at some point? Any advice will be greatly appreciated. I read all your colums in the RJ that you write. Lots of excellent advice there. A. Flowering plums can handle the rock better because you aren’t really worried about a crop of fruit to eat. But the rock on top of the soil will aid in the depletion of organic matter and over time it will most likely turn the pinkish color that accompanies iron chlorosis in red leaved trees like the purple leaf plum. If not corrected that can lead to more of a decline in the tree opening it for dieback and insect/disease problems. This is the purple leaf flowering plum when it has iron chlorosis. Plants with green leaves will have their leaves yellowing with green veins. In plants with purple leaves the leaves will turn pink instead of yellow but the veins will still be a darker color than the leaf blade Bark mulch is not nearly as effective as plain old ugly mulch made from chipped landscape trees. Not many nutrients in bark, it decomposes slowly, and is all just about the same size so it doesn’t decompose as effectively as chipped wood mulch. Plus 28 inch diameter irrigation basin is not very big. As these trees get bigger they will need more water. Increase the basin to about six feet in diameter (three feet from the trunk) all the way around the tree and fill this basin which should be about three to four inches deep. Fill it twice with each irrigation. Hard to say why the bark is splitting and falling off but I would pull the loose bark off and look for damage to the trunk such as holes for borers. The bark should be removed anyway of the trunk is dead under the bark and it is pulling away from the trunk. Often this type of situation turns into a long lingering death spiral for the tree over the next few years when it will decline more.

Fall Lawn Replacement in the Hot Desert

Leave a Comment / grass, tall fescue, turfgrass / xtremehorticulture

Upper surfaces of grass blades can help identify which type of grass it is: L to R, Kentucky bluegrass, perennial ryegrass and tall fescue Q. I need advice. We planted about 100 square feet of sod a couple of years ago. It had been doing quite well. I believe it was over fertilized 5-6 weeks back.. It is now very brown and not responding to watering. I plan on replacing it with new sod once it cools down. My question is, can I put the new sod over the old or pull out the old and re-prep the sub base? Any advice would be appreciated. Sod removal using a sod cutter A. You didn’t say what kind of sod it is but I am assuming it is tall fescue. Tall fescue represents about 98% of all lawn grasses in the Las Vegas area due to its tolerance, for a cool season grass, to our high summer temperatures. Before you do anything make sure it is dead. Tall fescue can appear dead but if you see any green at all at the base of the dead grass then it may just have died back. Tall fescue is very drought resistant even though it uses a lot of water. It can dieback when water is not available and sit there for quite awhile appearing dead and then re-emerge from grass that looks dead and start growing again. This might take a couple of weeks of applying water after it turned brown. It might then be a bit sparse and you may have to seed into the grass again to get it to fill in those bare areas that didn’t make it. Power rake, aka dethatcher aka verical mower used for removing thatch, slicing stolons and improving water penetration to turfgrass or lawn. However, if it did turn brown due to a heavy fertilizer application then that is salt damage and tall fescue is not all that good in its tolerance to salt and then it is very probable you are right. You have two alternatives in replacing the sod. One is to rent a sod cutter and cut the old sod out leaving behind a ready made surface for resodding. Or you can try digging it out by hand and leveling the surface in preparation for the new sod. A lot of work. You will not be able to put new sod on top of the old sod. The old sod will leave an “interface” that will cause all sorts of problems for the new sod. There is still yet another alternative worth considering. The dead grass is a perfect seedbed for seeding a new lawn. In about late September to mid October mow your dead lawn as short as you can and use your bag on the mower. Don’t mulch the dead grass back into the dead lawn. Next rent a power rake, sometimes called a dethatcher, and dethatch the dead lawn deep enough (you can adjust it) so that when you make a pass or two you can see soil between the dead grass blades. It is important to see bare soil throughout the dead lawn. Patchy look to a lawn when a coarse textured grass is seeded into a finer textured grass. An example would be seeding K31 or Kentucky 31 tall fescue (a pasture grass) into bluegrass or even a turf-type tall fescure with a finer texture Purchase good quality tall fescue grass seed, 100% tall improved tall fescue and not Kentucky or K31 tall fescue, the cheap stuff. Apply a starter fertilizer such as 16-20-0 or any fertilizer high in the middle number(in this case 20) but having some of the first number (in this case 16). Seed at about 10 to 12 lbs of seed per 1000 square feet and topdress it with topdressing or steer manure with NO MORE than about 1/8 inch of topdressing. It is best to do this with a roller for applying this stuff. You can rent one from most rental places. Irrigate about three times a day for a few minutes each cycle. Irrigate long enough to wet the topdressing but not long enough to cause it to run off of slopes or puddle. Do this about 8 am, 1 pm and 6 pm. Your biggest challenge will be keeping the pigeons and other birds off of your seeding. Reduce your watering to once a day when you see grass emerging usually in 7 days or less. A wild idea would be to not use tall fescue but a different grass seed that has high tolerance to heat in our area and a much softer feel to it. These are the heat tolerant perennial ryegrasses. They are superior to tall fescue in feel and water use but you have to get the right kind of perennial ryegrass. Some perennial ryegrasses are very heat tolerant and others are not at all and will burn up when it gets hot in the summer. One of the best of the perennial ryegrasses is a combination of Palmer and Prelude perennial ryegrasses. It has been used on golf courses for nearly 30 years now here and does very well in the heat. You can mow it short as close as ½ inch or less (if you seed at the right rate for this kind of cut) or even up to two inches. It is soft to the touch, unlike tall fescue which has tiny hooks on the edges of the leaf blades that can cause “itchiness” some people think is an allergy which it is not. The problem is that it is only available in 50lb bags. This seed blend is available in Las Vegas from Helena Chemical Company but it will be pricey in that quantity. I could not find it on the internet in smaller quantities.

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Newly Planted Apple Tree Dead

Leave a Comment / what causes apple trees to die when planted, why did my fruit tree die, why did my new apple tree die / xtremehorticulture

Q. I’ve attached a picture of what was once a beautiful, thriving Golden Delicious apple tree. Within one week it turned brown and died. It’s a young tree. I didn’t plant it myself I purchased my home last July and it had just recently been planted. A. Because the entire tree died from top to bottom we can be relatively certain the problem was at the very bottom of the tree, in the trunk or the roots. The most common reasons are watering too much or too little, planting the tree too deeply, and leaving mulch piled around the trunk when it is young. First, manually run the irrigation cycle and make sure that water is getting to the tree. If that cycle is operating normally and other plants on that cycle seem to be doing fine then we can probably eliminate watering. But you must check this first since this is the easiest one to eliminate. Next, let’s eliminate planting too deeply and problems with the rock mulch. Get something to kneel on and pull the rock mulch away from the trunk. With your fingernail or a penknife cut into the part of the trunk, just barely beneath outer bark, that was covered with mulch. Make the same cut into the trunk just above the bark or make one long cut to include both. Click on the picture to enlarge it. The young tree was dying back. I pulled the mulch away from the trunk and dug down about one inch into the soil next to the trunk and finally got some roots. Too deep. I scratched the trunk with my fingernail (you can see the scratch) and it goes from white/green at the top to tan/brown on the trunk below the mulch. Collar rot due to planting too deep. The color of the trunk just under the bark should be identical in color in both spots; white not brown. If the color just under the bark that was covered with mulch is brown, then the tree died from collar rot due to the mulch in contact with a young trunk. Never put mulch, whether it is wood or rock, directly against the trunk for the first four growing seasons. Keep its six inches away from the trunk until it is older. Lastly with the mulch pulled away from the trunk and still on your knees, dig the soil away from the trunk until you find the first roots. These first roots should be no deeper than about ½ inch below the soil. If roots coming from the trunk are deeper than this and soil has been placed around the trunk and the part of the trunk covered by the soil was brown, then it died of collar rot because it was planted too deeply, a common mistake. Always plant all trees and shrubs with no more than ½ inch of soil covering the roots and make sure the tree is staked the first growing season.

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Figs Grow Great in the Mojave Desert

3 Comments / Uncategorized / xtremehorticulture

Q. A friend of a friend has two fig trees that produce just the best figs I have ever tasted. So I am planning on taking cuttings and eventually planting them in my big back yard with full southern exposure. However we do not know what variety they are, so is there an easy way of identifying them and knowing whether they are self-pollinating, i.e. whether I need to plant two of these trees? A. All of the figs I have tested here in our climate do well with very few problems. It is just a matter of your preference in taste. Normally, the darker colored figs such as black mission or brown Turkey have a stronger flavor. The yellow or white figs are milder in flavor. The biggest mistake when growing figs here in our climate is not watering them with enough water during each irrigation. They are oasis plants, not desert plants. One of our “white” figs, perhaps ‘Desert King’ Nearly all figs are self-fertile so there’s no need to have more than one. There are so many different varieties of figs it would be very difficult to identify which fig it might be. However, if you send me a picture of the fresh fruit so that I can see outside fruit color and color inside the fruit (cut open) I might be able to narrow it down for you. Also, let me know if it was purchased through a local nursery since they typically carry the more common varieties. This also helps narrow it down. Follow my blog and I will give you some step by step instructions on how to propagate figs and grapes as well in the near future.

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Lowering the Height of a Large Tree

Leave a Comment / can i remove limbs, middle of the tree, pruning large trees, removing limbs from trees / xtremehorticulture

Q. I have a view of the valley for a few months of the year when the leaves of many trees behind my property are gone. The partial view is still manageable the rest of the year except for a tree that is very, very full and you can see nothing beyond or through it. I know I can’t ask for that tree to be topped. But what would happen if I asked for some branches to be removed in the middle of the tree so that it wouldn’t be obvious to anyone? Before I go before a Board and ask such a question, I would appreciate your views on doing this and what the consequences might be down the line. A. If the tree is pruned using a method called drop-crotching by a certified arborist then you should have no problem with the tree and still maintain its beauty. However most “tree-trimmers” will not know this technique but a certified arborist should.You can remove limbs from the center of the tree as well to “open it up” but be careful of the tree you do this to. Some sunburn easily. I know you wont be allowing this to happen but this is a common occurence here. The technique is the lowering of a tree’s height or removing portions of the canopy by removing entire limbs at the point where they originate inside the canopy. This technique preserves the trees silhouette, general shape and reduces suckering while still accomplishing a smaller canopy. There are tree butchers out there who have no regard for trees but only concerned with the destruction they can accomplish with a chainsaw. Whether it is a certified arborist or a tree trimmer, if you’ve hired a good one, the removal of a portion of the tree’s canopy will result in a smaller tree but leave you wondering if it was pruned at all. This pine tree was opened up for power and telephone lines and look what happened. Be careful. One of the best arborists I have ever had the privilege to work with was as an artist with trees. A former trumpet player, he started nearly 30 years ago in landscape maintenance but did some of the best tree work I’ve ever seen and went on eventually to be a certified arborist with the city of Henderson. He has passed on since then but those “tree artists” are out there. Those are the ones you want to hire, not the butchers. These tree artists are proud of their work but sometimes get criticized because the people who hired them paid them a lot of money and the work that they did was not obvious when they were finished. That’s how good they are.

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My Lawn Is Watered Enough It Has To Be Bugs!

5 Comments / Uncategorized / xtremehorticulture

Q. Do I have a bug problem? Spots in various areas of the lawn. I water enough. Lawn suffering from a lack of water. Brown areas are undefined and kind of run into each other. Pattern of damage is related to the irrigation pattern. A. So if you believe you water enough let’s go ahead and eliminate the possibility that you underwatering, overwatering, and getting even water coverage over the entire lawn through a properly designed and installed irrigation system. That system should have what is called head-to-head coverage (water from one sprinkler should be throwing water all the way to the neighboring sprinkler) and a pressure regulator should be on the system so that water pressure at the sprinklers is not excessive. This helps prevent misting due to excessive water pressure. This is the lawn disease called “summer patch”. It has a definite pattern to it. Kind of horseshoe-shaped or the brown damage has a green patch in the center. Can you see the pattern? Brown spots from watering problems usually occur in the same spots year after years and do not “move around” in the lawn. These spots are usually either next to the irrigation heads, halfway between heads or along the edges of an irregularly shaped lawn. So now that we have eliminated those problems since you water enough let’s move on to “bugs”. “Bugs” will usually include either insects or diseases. In tall fescue, the most commonly planted lawn grass for homeowners here in our valley, this is the time of year for disease problems. The most common lawn disease right now is summer patch and often accompanies our “summer monsoon” season. Here is “summer patch” when you look at a bunch of the running together. We say the pattern has “coalesced” resulting in tufts of green grass growing in among the damage. The spots start out as brown patches about 8 to 12 inches in diameter and frequently shaped like a partial circle or horseshoe. As this disease advances these brown spots blend together, if there are enough of them, into a wiggly or “snake” pattern of brown, dead grass. If you look at the green grass in amongst the dead grass, the green grass will be in circles about six to eight inches in diameter. Make sure you are watering a few hours before sunrise, giving the lawn a chance to dry out as the sun comes up. Mow at 2 to 2 ½ inches in height. You can apply a fungicide that includes summer patch disease on the label and follow label directions.

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