Q. First year with my apricot and I spray with soapy water to control aphids. Every day I check leaves but they never stop. Is this good to spray to use? Adult aphid. These are about the size of a large grain of salt. There are about 200 different aphid types and most of them only prefer a specific plant. A few of them are general feeders but most are very specific to what they like to eat. A. Soap sprays are good to make an immediate kill of an insect and don’t expect them to reestablish themselves after you’re finished. The problem with aphids this time of year is that they will come back, usually in just a few days, after soap sprays have been applied. Aphid feeding on plum leaves can cause the leaves to curl over time, thus protecting them from sprays. I am not a big fan of soap and water sprays for insect control but if you decide to make your own please use a Castile type soap free of any scents or lotions. Use a decent soap The good thing about soap sprays is that they are very safe for humans, pets and other large animals. The bad thing about soap sprays is they do not discriminate between good bugs and bad bugs. If it’s a bug and you spray it, it will die, good or bad. Soap and water is a killer             The second negative about soap sprays is they have no residual. That means that soap sprays leave nothing behind to kill bugs after the spraying is done. They have no residual. You are the residual. Soap sprays rely on you, the applicator, re-spraying when needed.             You must be knowledgeable enough to spray the bad bugs but not the good bugs. It also requires that you find most, or all of the bad bugs when you spray. If you don’t, they reestablish in a few days and you must spray them again, and continue to spray them as long as you need to, over and over, until the problem is gone. More about aphids             Aphids began infesting new growth, making more babies, as soon as the leaves popped out. Females that survived and made it through the winter on landscape plants had wings. They flew to the soft, succulent, sugary new growth and started laying eggs as soon as it came out and as fast as they could. What a good mother! Ladybird beetle with aphid             Mature female aphids that make it through the winter have wings. They can fly short distances to the new growth. These mother aphids never need a male aphid to produce their young and they produce young very rapidly. Aphids on developing pomegranate fruit. The fruit tissue is pretty hard for them to feed through but they will certainly like the much softer leaves and flower petals             It just so happens that many ants like the sugary residue that aphids leave behind when they are feeding. Those ants which use sugar for raising their young absolutely love aphids and move them to different locations on plants so that they can “farm” them. Controlling ants colonies also helps to control aphid populations. Chemical controls             Moving up the line of toxicity to aphids and comparing it to the toxicity toward humans and the environment, next try some of the oils such as neem oil, rosemary oil, mint etc. next moved to the so-called “organic” or “natural” sprays like pyrethrins.             Pyrethrins are made from a type of chrysanthemum. If you feel safe with pyrethrins, you may choose to move to the synthetic pyrethrins which are everywhere in garden stores but are not considered “natural” or organic. They leave behind a residual and continue to kill insects after they have been sprayed.

Q. So how do we eradicate poa Anna? Annual bluegrass in a hybrid bermudagrass home lawn. Notice the discoloration by the Poa when the bermudagrass is actively growing. A. Poa annua or annual bluegrass is easy to control in landscapes but extremely difficult to control in most lawns. If this is in a lawn such as a cool season grass like tall fescue, Kentucky bluegrass or perennial ryegrass it is very difficult to control. This is the worst situation. If it is growing in 100% Bermuda grass it is much easier to control. If it is growing in a landscape, around trees and shrubs, it is easy to control with mulch.   Annual bluegrass persisting in hybrid bermudagrass on a golf course during the winter months. Annual bluegrass stays green during the winter in colder climates while the bermudagrass becomes dormant, dies, or turns brown. Annual bluegrass has evolved.  This grass is very different from what it used to be 50 years ago in many locations. In the old weed control manuals 30, 40 and 50 years ago they all said the same thing. It is a winter annual, the seed germinating toward the end of summer, flowering or producing seed heads during the fall and winter months and the seed laying dormant or sleeping through the summer. It repeats this cycle over and over. Annual bluegrass is a very poor competitor with mulch but it is an excellent competitor when it grows among other grasses. When I went to school, this is what I learned annual bluegrass was.   Annual bluegrass seedhead. Annual bluegrass has evolved in certain landscapes and climates where it now persists as a perennial in warm climates and will produce seed at different times of the fall and winter months. This is very apparent on many golf courses and a nightmare for golf course superintendents. This grass can be mowed very short, 1/4 inch or less, so mowing it out will not happen. It loves environments where the grass is mowed short and kept wet. It is also very strong in soil environments that are compacted without much airspace between soil particles. I would compare it, from an evolutionary standpoint, to the cockroach. Controlling it in cool season lawns. When it grows in cool season lawns, the usual methods of control are pre-emergent weed killers or herbicides. If this is a home lawn, you will have an advantage because you can apply these pre-emergent herbicides several times during the year and that’s what you will probably have to do, starting in late summer and through next spring.  Look at the pre-emergent herbicides available to you and select one that can be applied to a lawn and says that it controls annual bluegrass. Make the first application of pre-emergent herbicide in the middle of late summer. In the hot, southern Nevada climate this would be about mid July or early August. Read the label and it will tell you when to make a second application and how much to apply. In the past, Scotts has made excellent products for weed control in lawns. Pre-emergent herbicides slowly degrade over time. You want to apply this herbicide a short time after its peak control period. It will tell you on the label how many weeks to wait after this first application before the second one is made. There is some residual from the first application so you will make the second application at some rate less than the first application. I repeat, the label will tell you how much to apply and how long to wait before applying the second application. Continue this cycle of applying, waiting and repeating all winter long (if the label allows it) and into early spring. That should kill most of the seed. If you see some young plants that were missed by the herbicide application (they are usually lighter green and grow faster than the surrounding grass) then pull them by hand. They will pull out easily because they have very shallow roots. Annual bluegrass biotype producing short rhizomes, adapting like a cockroach to a changing environment. If this is a bermudagrass lawn, kill the annual bluegrass during the winter months after the bermudagrass has turned totally brown (dormant). Do not overseed this bermudagrass lawn with a winter lawn this year, and possibly the next year, until you get control of the bluegrass. By the way, this is also an excellent way to control other weeds including tall fescue growing in a bermudagrass lawn. After the bermudagrass lawn has turned all brown, and you have mowed it, spray the lawn and the annual bluegrass in it with Roundup herbicide. The Roundup will kill the annual bluegrass because it stays green during the winter months (cool season grass) but the bermudagrass is dead above ground. The Roundup will have little to no effect on the dormant bermudagrass. This is a core aerator that punches holes in the lawn. Management methods that help to suppress annual bluegrass are aeration (punching holes in the lawn with a core aerator) and waiting longer between irrigations during the late summer, fall and winter months. Aeration helps open the soil which annual bluegrass does not like. As I said before, annual bluegrass likes it wet because it has a very shallow root system. Waiting longer between irrigations helps keep the soil dry and minimizes its invasion. Preventing annual bluegrass from entering your landscape and lawn should be done in the future. The seed is transported to the landscape on shoes that walk across the seed heads during the fall and winter months. If a landscape has annual bluegrass and people walk across the seed heads and then walk into your landscape, they will transport the seed and that’s where it starts. It is also transported to lawns in the same way as well as the lawnmower. If a lawnmower was used on a lawn that had annual bluegrass in it and it was seeding, I guarantee 100% that this

Q. You mentioned to drill holes in the trunk of the Cypress and pour a solution into the holes to encourage decay. Can you tell me again what that solution was? I can’t read my own writing! A. I would use diluted Roundup if the tree is still standing and you want to kill it. Use the most concentrated form allowed on label. Either buy it in the diluted form or dilute a concentrated form but do not use it full strength unless it is already diluted.             Drill the holes as close to the ground as you can and at a downward angle. Use something like a syringe or other disposable item to force dilute Roundup down the holes that are freshly drilled. Fill the holes every hour three times to get plenty of chemical in the tree if you want to kill it.Make sure you wear unlined gloves during the application to protect your hands.             There is a product that you can buy which you can apply to the stump after the tree has been cut down. Once the tree has been cut down, drill holes in the stump vertically and fill the holes with this product.The product comes under several names such as Stump Remover, Stump out, etc. Follow the directions on the label. Hope this helps.

Q. Hello again!  I have a puzzling issue happening with a few citrus trees (out of many).  The leaves are curling, yellowing, and ultimately dropping. I attached a few pictures in hopes you could shed some light on the issue. (Any iron deficiencies you see are from trying to extend the time between treatments, something I’ve been trying to perfect; seems like every 6 weeks is the sweet spot.) I appreciate any help you can give me, I’d hate to see these trees die!  Leaf rolling like this on citrus can be a watering problem Add caption A. If the leaves are rolling or curling into a cigar shape, then this is typically a lack of water. The leaves can turn yellow and drop from the tree if it continues. A lack of water can be from not giving each tree enough water or it can result from not watering frequently enough.  Strangely, the same can result if you are watering too often but it almost never results from giving a tree too much water in a single application. My suggestion to you, if these trees aren’t drip emitters, is to make sure that each tree has at least four drip emitters.  Replace these emitters with emitters that double the application rate. In other words, if these are 2 gallon per our email letters, replace them with 4 gallon per hour emitters. This allows you to keep the same number of minutes on your irrigation timer and not overwatering other plants on the same valve.  I would strongly advise you not to use adjustable drip emitters for this purpose. They can be extremely difficult to adjust properly since they seem to act like “whack a mole” when you try to adjust them. Visit this page from the University of Arizona on citrus problems in the landscape

Q. I have a high brick wall in my backyard that has white crystals, or “whiskers”, forming on it.  This is because of the over watering by my neighbor on the other side of the wall.  I asked my neighbor if they would decrease their watering but that hasn’t happened.  I have used vinegar and brushed it off with a stiff brush. I also tried brushing it with a dry brush.  They are not working.  I bought some muriatic acid, but I am afraid to try it because I have plants and trees right by the wall.  I would appreciate any advice you can give me to solve this problem. Soft deposits on a porous wall are “fuzzy” or can look like white whiskers. A.  You are correct.  This white, “powder” or “whiskers” is because of the water coming through the wall from your neighbor.  When the wall dries, white “salts” are left behind on the surface of the wall which were previously dissolved in the irrigation water.              The only long-term solution is to reduce the amount of water applied on the other side of your wall.  Eventually irrigation water coming through the wall and containing salts will undermine the strength of the wall. Phosphoric acid is better for the plants than muriatic acid             I am afraid this is a common problem with no easy solution if your neighbor is not willing to help.  In the meantime, use phosphoric acid rather than muriatic acid to remove white “whiskers” from the wall.  Phosphoric acid is safer to use and the phosphorus contained in the acid is a plant nutrient.              Muriatic acid contains chlorine, also a plant nutrient, but needed in very small quantities by plants compared to phosphorus.  Chlorine can be toxic to plants if too much is available.               Ultimately, your neighbor’s landscape should have a “dry zone” at least 3 feet wide next to this wall.  This dry zone does not have to be void of plants.  It can contain water conserving plants irrigated with drip emitters.  Minioasis landscape design             An even better solution is to convert this landscape to a “desert landscape” using a minioasis landscape design.  Minioasis landscape designs feature high water use areas of the landscape close to the house, located where people like to congregate.  The other areas are designed and landscaped to use less water by having fewer and smaller desert adapted plants.

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.