Q. What’s wrong with my tree? The tree is dying from the inside to the outside.  I can see dead wood on the inside that is rotting through a big hole in the side of the tree. All trees that are not in the grass family, such as palm trees, are dead on the inside and the living part is just under the bark. A.  Older trees are dead on the inside and have a cylinder of living tissue just under the bark.  If the dead wood inside of the tree becomes infected with wood-rotting microorganisms, they can consume the entire inside of the tree, eventually leaving it hollow but alive.              The center of the tree can get infected with these microorganisms when large branches break or they are removed with an unsanitary chain saw.  It is important to remove broken branches as soon as possible with a sanitized chainsaw or hand saw.  The remaining wound is left to heal on its own without any sealer being applied.             The dead wood inside the tree has little chance of fighting off wood-rotting microorganisms.  Once infected, these microorganisms spread easily through the dead, internal parts of the tree.              These microorganisms do not invade or damage healthy, living parts of the tree.  Keep trees healthy with appropriate irrigations.  Fertilize them once a year in early spring.  Sanitize and sharpen any tools that cut into any healthy parts of the tree.  

Q. Can you tell me if this tree will survive and what I need to do we have three purple plums and do not want to loose.  A. Judith. Let me tell you what I think happened and then I will explain whether it will survive or not. This tree appears to be the purple leaf Plum. I see some branches coming from this large limb on the upper surface of it. Perhaps the started growing about three years ago? There is damage to at least one side of this limb. My guess is that this damage faces the South or West. I am guessing that several years ago this limb received sunburn damage to this side. Shortly after this damage or possibly even before this damage, boring insects or borers entered this limb. The female borer is a small beetle about 3/8 inch long and she deposits her eggs close to these damaged areas. This borer damage started as sunburn to the trunk of this ash tree. The young from these eggs burrow into the limb where they feed on the soft, juicy, sweet tissue just under the bark. This feeding causes the limb to die in a larger area usually only near this sunburned area. Areas not in direct sunlight, like the top and bottom of the limbs, are usually not damaged. Borer damage to ornamental plum again for the same reason, it started with the sun damage and then progressed to insect damage. I cannot tell how much damage this limb has without a closer look but I am guessing it is not bad enough to remove unless there is extensive dying of the smaller limbs attached to it. You can apply an insecticide around the base of the tree called Bayer Advanced Tree and Shrub Protect and feed which will kill the boring insects inside the limb and protect the tree for as long as 12 months. This may give the tree enough time for recovery to begin. A word of caution: the active ingredient in this insecticide has been implicated in honeybee decline but not proven. There is evidence both pro and con. But it is best to apply this after the tree has finished flowering. Make sure the tree has enough water so that it is not getting water stressed. This means make sure there are enough drip emitters or they are large enough to support the tree. This tree probably needs somewhere around 30 gallons each time it’s watered. Watering once to twice a week is enough. Around May, that will change to two three times per week. This tree grows best if the top of the soil under its canopy is covered in 3 to 4 inches of wood chip mulch, not rock mulch.

Q. I came from Southern California where I had beautiful red and yellow bougainvillea that grew with little help. I tried to save my beautiful pink bougainvillea last year by moving it onto my patio close to the house. I covered it every night, uncovering it in the daytime. It appeared dead this spring but just now I see some very tiny green leaves close to the bottom. Do you think this bougainvillea can come back? Even a light freeze will damage bougainvillea like this. A. Yes, it will come back. Bougainvillea is a frost indicator plant. In other words, if the temperature drops one degree below freezing, you will see damage to this plant. If the temperature is freezing for several hours combined with strong winds, it will die to the ground.             Bougainvillea frequently dies to the ground each winter it freezes and resprouts from its “crown” in the spring. The crown is where the top attaches to the roots and grows just below soil level.             After the first freeze in the fall, cut it to the ground and cover the area with 3 to 4 inches of woodchip mulch. I will sometimes use a nursery container turned upside down with the bottom cut off. I place this over the trimmed bougainvillea and fill it with mulch.             Never fertilize bougainvillea after August 1. High nitrogen fertilizers make sensitive plants more tender when the freezing weather comes. But always continue to water it through the winter months every 10 days to two weeks. ‘Barbara Karst’ Bougainvillea With leaf cutter be damage             As soon as freezing weather has passed (tomatoes have been planted), uncover it and let the sun warm the soil. As soon as you see new leaves sprout, fertilize it or apply compost. One fertilizer application is probably all it will need for the whole year. 

            Let’s talk about wind damage. If you didn’t sustain wind damage to your landscape, you are extremely lucky. It was fortunate these high winds occurred early in the season and many trees were not yet full of leaves. If it had been a few weeks later, the damage would have been worse. Ornamental Plum, wind damage to the leaves             New leaves just coming out were shredded by these winds or new young shoots were broken. You might not see the damage at first but after a few days the damage will turn brown. Seeing this, you might think insects or diseases. Don’t worry. Some light pruning will remove the damage and new growth will cover it in less than a week. Wind damage to persimmon on the lower leaves while the new leaves (closest) that emerged after the wind are undamaged             Branches and trunks of trees split or broke. If you think you can bandage the damage, think again. If the wood inside of the split has dried, even for a couple of hours, joining the two together will not heal the split. It’s a goner. Peach wind damage to the leaves.             You might be able to salvage the tree by cutting below the break on the trunk. See if it will begin suckering beneath this cut. Make the cut about 1 foot above where you want new branches to emerge. Corn wind damage blown over             If a branch split, cut it back to a side branch. Whether it will grow back or how it will grow back depends on the kind of break, where it occurred and the type of tree. If it is aesthetically important to the landscape, remove it and replant. It could take years before it will look good again unless it is a fast grower.             Leave shredding and breakage also happens to vegetables. Most can be pruned, a very light application of fertilizer and watered to help them regrow.

Q. I was just reading up on the leaf footed plant bug and came across this link: http://ipm.ucanr.edu/PMG/r3301011.html Does this mean that bifenthrin is their top choice for chemical control? Is synthetic pyrethrin (what I am using now) the same or similar? I see that some Ortho products for lawn and garden contain bifenthrin. Could those be used to spray the almond and pistachio every 2-3 weeks until it gets hot (and early or late in the day when bees are not present). Leaf footed plant bugs mating on pomegranate. Please don’t stare! Leaf footed plant bug on citrus Leaf footed plant bug on edible prickly pear cactus, tunas and nopales Leaf footed plant bug wee one, Highly enlarged, courtesy Auburn University A. Good detective work. Yes, Bifenthrin is a synthetic pyrethrin or pyrethroid (the chemical name ends in -thrin) and it gives good control of leaf footed plant bug as does pyrethrin. Sevin insecticide also gives pretty good control but is also lethal on honeybees. Bifenthrin: Highly toxic to bees so always spray either on a cloudy day (lots of luck here) or at dusk when bees have gone home.  Protect yourself. It has a low toxicity to humans but it is still a poison. Protect your face mostly because it enters the body most easily through moist tissue (nose, mouth, ears, etc). Whatever you use, follow the label on when to respray and stop spraying the number of days it tells you for harvesting.  Unfortunately this insect is not easily controlled since it has wings, can fly and come from or go to neighbors. They may be spending the winter as adults on evergreens on your property. Not pines but broadleaf evergreens like bottlebrush. http://npic.orst.edu/factsheets/bifgen.html Its also really good at controlling home pests like cockroaches, black widows, scorpions, etc.

Q. 1) what should the watering times be for Vegetable beds planted with typical vegetable seeds at this time of year? 2) Should the length of time be different when the beds are first seeded, as opposed to a month later when there are plants growing? 3) How should those times change seasonally with the temperature changes, that is, spring, summer, fall and winter? A. Those are great questions and thank you for asking them. I hope that you will take my suggestions as just suggestions, and not as the “gospel”. It’s better if you use these as starting points and adjust my advice to fit your needs. I use 1/2 inch drip tubing with the emitters embedded into the walls of the tubing every 12 inches. I use 1 gallon per hour emitters.  When installing this drip tubing, I make sure that the neighboring irrigation emitters offset the neighboring emitters by 6 inches. In other words, the emitters are spaced from each other in a diamond or triangular pattern. Drip tubing with embedded drip emitters every 12 inches and spaced in a diamond or triangular pattern on a raised bed without permanent sidewalls Let me go through a list of general rules that I use and let’s go from there. I soak large seed such as corn, peas, beans and even garlic cloves in tepid water for several hours before I plant it. The first step in seed germination is the uptake or imbibition of water. Doing this can speed up germination and reduce it by two or more days. Otherwise, you have to keep the soil constantly wet and can be nearly impossible for seed germination when air temperature gets above 90° F.   Raised vegetable bed mulched after seeding and irrigated using drip tape. I mulch the area where seed is sown with a 1/2 inch layer to help keep the soil and seed wet. I have tried a number of different mulches including sand, straw, compost, perlite, vermiculite, and peat moss and found that bedding used for horses (pine shavings) to be the best. These thin shavings “dissolve” into the soil over several weeks while straw does not and can sometimes interfere with soil preparation. This can be bought at Viragrow (www.viragrow.com) or any farm supply stores.  Seedlings mulched with horse bedding, pine shavings, to help preserve a soil moisture after seeding and seedling emergence. I work with 12 inch spacing so the number of minutes of run time may be shorter or longer for spacing different from this. The number of minutes should be long enough to get water the entire 12 inch depth each time you water. Use a soil moisture meter (like for houseplants) to see how deep it goes.   Houseplant moisture meter used to gauge the depth of watering. Surface mulch helps when starting plants from seed in containers. 1) what should the watering times be for beds planted with typical vegetable seeds at this time of year? Make sure the seeds are planted the proper depth and it’s best if they are covered with a 1/2 inch layer of horse bedding/mulch. If it is, you can water daily for 30 minutes. If you don’t cover it with mulch, small seeds planted shallow, water three times a day for 15 minutes each. Large seed, 1 to 2 times per day for 15 minutes. It’s easier with mulch. After the seeds germinate and you see their first true leaves, switch to once per day. Seedling emergence through the surface mulch. Drip tape used for irrigation. 2) And, should the  length of time be different when the beds are first seeded, as opposed to a month later when there are plants growing? A month later you could be watering once a day at 8:53 AM just before it starts to get warm. You want the plants to have access to water before he gets warm or windy. If these are smaller plants, water them for 30 minutes. If these are large plants, water them for 60 minutes. The progression of watering is from frequent, shallow irrigations after seeding or transplanting to deeper more widely spaced irrigations as they get more mature and bigger. 3) How should those times change seasonally with the temperature changes, that is, spring, summer, fall and winter? Plant water use increases by 400% from the first month, January to the sixth and seventh months, June and July, in Las Vegas Nevada. Inches of water per day. Water use in December and January is about 1/10 of an inch per day. In June and July it is about 4/10’s of an inch per day, a 400% increase. The change is in the frequency water is applied, not necessarily the number of minutes. So, after germination and establishment the water might be on for 60 minutes in December, the same amount in July. The difference is that watering in December might be every four days while in July it is daily. Mulch, as I described above, really helps a lot when temperatures get above 90° F. You will see a difference in the plants when mulch is applied to the soil surface. Pine shavings such as horse bedding disappears in about 2 to 3 months and needs to be renewed. With mulch applied, daily irrigations are enough during the middle of summer. If no mulch is applied, you will probably have to irrigate twice a day; once in the morning For 60 minutes and a second one midafternoon for another 60 minutes. These irrigations will be different if these raised beds were not amended each year with fresh compost. Amending them each year keeps the pore spaces in the soils open and plant roots will grow deeper. Plants with deep roots are less likely to become stressed during the heat. Moisture meters like this one for houseplants are very inexpensive and not very accurate, but accurate enough to gauge if a soil is wet, moist or dry. The moisture sensor is in the tip

Q. Is there a mulch will not lower the pH of my garden beds as it decomposes? I have Goji berry plants which do best at a pH of 6.8 to 8.1.  I want to use something to protect the soil from the summer sun and to prevent the winds from blowing the soil away.  A. Surface mulch always lowers pH as it decomposes. In normal desert soils, you can expect it to drop to about 7.6.  Hopefully you used a good compost when you amended the soil at planting. This will also help a lot. If you want to drop it more than that you have some options such as sulfur that has been ground to a dust rather than large granules.  Soil sulfur is granular sulfur and slowly breaks down in soils. Its effect at lowering soil pH is minimal at best in desert soils. Water dispersible or degradable sulfur is like a powder or dust. Because of its small size and large surface area, it breaks down very rapidly in warm soils and is a bunch better choice to lower soil pH than granular sulfur. An example is Dispersul which is water dispersable sulfur. Should sell for about $1 per pound or so. Sulfur granules just sit there and don’t dissolve in our soils and about the same price. Sulfur needs moisture and warm soil temperatures to work.  I was surprised when this product dropped the pH of water down to 3.5 in about 15 seconds. It doesn’t need warmth or microorganisms to work. The other is a product I have worked with called Garden Magic which drops the soil pH without warm soils. It will drop pH in water to about 3.5. Works very very well and also sells for around $1 per pound and it is in a $30 bag. I think the Dispersul is a 50 lb bag. Both you can get at Viragrow in North Las Vegas. I don’t think any other retailer carries it. They all carry sulfur granules instead. The other option is aluminum sulfate.

Q. I am considering planting three, 22″ box African sumacs along a 40′ block wall behind a 1.5′ retaining wall. Is this feasible? How far away should they be from the block wall? Is there a better option for shade that isn’t poisonous to dogs and that have no invasive root issues? African sumac planted near a wall flowering in February  A. 80% of all landscape plants are poisonous. If your dogs eat enough of any of your plants, they can get sick.  Plant them no closer than 3 feet to the wall and 4 feet would be better, and 8 feet is ideal. This tree can grow to 40 feet and consumes a fair amount of water. These trees are really not intended to be used for planting along tall walls because of their shape.  Put your permanent irrigation away from the wall so that roots will grow in that direction and less towards the wall. It is very difficult for me to make plant recommendations when I don’t know what is available. Consult sites such as the plant list found at the Las Vegas Valley water District  and consult with your local nursery about availability of the plants that you like.

Q. The second pertains to the attached photo. Specifically, what will it develop into? I found only one of these, about 6″ down as I turned over my garden beds. The last thing grown in the raised beds were two very successful crops of grape tomatoes. One in the spring, and another from the same plants in the fall. Tomato hornworm pupa Tomato hornworm larva before it turns into the pupa Sphinx moth or Hummingbird moth, the adult which he emerges from the pupa. These 3 inch long moths fly at night and at dusk visiting the flowers of plants just like a hummingbird, hence the name. A. The photo is the pupa of the humming bird moth aka tomato hornworm as a larva. Voracious feeder of many plants Including tomato, grapes and ornamentals.. A bad guy. Easy to control the larva with handpicking in home gardens. Easy to see at night with a black, UV light because the irridesce green under a UV light. Otherwise they blend right into the foliage of the plants and are difficult to see during the day.  Sprays of Bt (Dipel, Thuricide) or Spinosad. Don’t spray Spinosad during daylight hours because it is lethal to honeybees.

Q. After reading your list of recommended fruit trees I see that Fuji apple trees would do good in Las Vegas? A. Yes, they will do well. Don’t expect to get the same quality of Fuji Apple you might expect when grown in cooler climates. The tree as well is the fruit itself will respond differently in our climate because of higher light intensity, temperatures, lower humidity and our alkaline soils. Fuji Apple growing in North Las Vegas Nevada              Apples grown in our climate tend to have a thicker skin and more wax development on the outside. Expect to get fruit with a higher sugar content and less acidity. The fruit may not be first-class but it will be better than what you’re buying in the grocery store.             Most tree fruit is harvested too early; mature enough to meet the minimum requirements by the buyer but not fully ripened. You have the luxury of leaving the fruit longer on the tree where it will develop more sugar and flavor.