Xtremehorticulture

Turfgrass Dead Spots. Disease?

Brown spots or dead areas in lawns can be common during summer months. It might be a disease, but then again, it could be something else. The three primary reasons that lawns develop brown spots or dead areas are due to irrigation problems, the development of diseases and insect damage. Disease Problems. In the hot, Mojave desert of the Southwest diseases are less likely than in wetter climates but they sometimes still occur. Most lawn diseases in our hot, desert climate occur when high temperatures collide with increasing humidity in the air. This is not the only ingredient for a disease to occur. The lawn must be susceptible to that disease. Typical summer patch symptoms Diseases problems are best solved through prevention. This is through managing the lawn to minimize diseases and using the correct fungicide when a disease problem is imminent. We influence a lawn’s susceptibility to disease by how we manage it. Here are some management decisions that you can follow to reduce disease problems to your lawn. Try to implement as many as possible. 1.     Finish watering just before sun up. 2.     Mow at the proper height and use a sharp blade. 3.     Aerate two months before the heat arrives. 4.     Use compost-based fertilizers monthly. 5.     Disinfect mower blades if you mow a suspected diseased area. When you suspect a disease is occurring, apply a broad spectrum fungicide (fungicide that treats many different diseases) as soon as possible. Diseases that should be listed on the label include summer patch and necrotic ring spot. They might also mention diseases such as “frog-eye” and Fusarium patch.

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Turfgrass Dead Spots. Insects?

Brown spots or dead areas in lawns can be common during the summer months. It might be a disease, but then again, it could be something else. Could it be insects? The three primary reasons that lawns develop brown spots or dead areas are due to irrigation problems, the development of diseases and insect damage.  Insect damage. Probably the least likely of the three, and the most easy to detect, is insect damage. Most of the lawns in the Las Vegas Valley are turf-type tall fescues. Tall fescue is not a sod forming grass like Kentucky bluegrass. Instead, each seed produces a single plant. These individual plants are not linked together like they are with Kentucky bluegrass. Kentucky bluegrass sends out rhizomes, or underground stems, that pop up a distance away from the mother plant. When these rhizomes grow together, they form carpet-like sod that holds together. Because tall fescue produces only one plant for each seed that was planted, individual plants are not linked together. White grubs feeding on lawn roots of sod             This is important when diagnosing damage to a lawn. Insects that feed on the roots of lawn grasses, like white grubs, will cause areas of dead or brown grass. Because the mother insect lays a lot of eggs in one area, insect damage is usually localized in one or two areas. The eggs hatch, the young grubs begin to feed on grass roots and the lawn develops brown patches that correspond to where the grubs are feasting. The roots are severed by the grubs and the grass cannot get enough water so it dies in patches during warm or hot weather. One type of an adult of the white grub             Insect damage by grubs is usually in spots that are fairly well defined. Because the roots are severed, the grass can be lifted from the soil quite easily. Because tall fescue are separate, individual plants the root-severed, brown grass lifts easily from the soil. In the case of tall fescue, the grasses lift from the soil in the independently and separately from each other. In the case of a sod-forming grass like Kentucky bluegrass, they do not. Because they are linked together, the damage area lifts like a carpet.             When inspecting a lawn to determine if the damage is from insects or not, go to the edge of the damaged area, not the center of the dead spot, and pull on the grass plants lightly with a closed hand. If grubs causes the damage and it is tall fescue, many of the plants will lift easily in your hands; dead ones and green ones at the same time that were recently severed.

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Homemade Recipe Weed Killer From Reader

Q. A friend gave me the following recipe for homemade weed killer.                  1 Gal.  Vinegar                  2 C Epsom Salts                 ¼ C Dawn dish soap—blue original             Spray on weed in the morning after the dew is gone.  Be sure to wash the sprayer well after us because vinegar ruins the rubber gaskets.             My husband says that the salt could leach into areas that we don’t want to kill.  Also, will the above recipe kill all it comes in contact, grass and broadleaf weeds? I would appreciate your thoughts on this.  A. I am not sure it will work but give it a try. The Epsom salts is a safe salt to use, not like table salt which is more like what your husband is thinking about. Table salt is sodium chloride. Both the sodium and the chloride are toxic to plants and the sodium in particular can cause longer term problems with the soil.  Epsom salts is calcium and magnesium carbonate salts. Safe for plants and used on roses by lots of Rosarians. My experience with vinegar as weed killer is that the acetic acid has to be above 15% which is hard to find.

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Who Stole All My Almonds?

Q. Our almond tree was full this year. However, half of our crop was eaten by something. The nuts are not ready yet. They are still green and so hard you would need a nutcracker to crack the shells open. My husband picked the rest of the almonds so we at least had something to enjoy. Any ideas as to what’s eating the nut and cracking them open? A. This is most likely ground squirrel harvesting. Technically I think they are called antelope ground squirrels and they are very common in southern Nevada. We find them typically at residences near or bordering the desert or large expanses of desert landscaping or open lots.             In almond orchards ground squirrels can harvest an almond tree overnight. They are very active right now, chewing open the green, hard husk and taking the immature seed. Seeds right now are soft and sweet, not yet hardened. You will see lots of empty shells on the ground from these critters. Empty almond husks at the bottom of the tree’s canopy from ground squirrels             Ground squirrels continue to feed on nuts throughout the season. When the husk splits open, they steal the nuts a lot faster and store them away somewhere. It is usually safer to harvest the nuts as soon as they split open and not leave them on the tree to dry. Ground squirrel grape thievery             I know that these little guys look cute but they can be real pests if they get out of control. They will also steal grapes right out of bunches. Bunches with stolen grapes look just like you think they might look, a bunch with grapes missing here and there on the outside of the bunch. Antelope ground squirrel adding insult to injury             Control is not easy nor is it any fun. In commercial orchards they frequently use poison bait to help control the population. There are other options such as trapping and relocation.             Please be very careful when dealing with ground squirrels. It is rare but they can transmit the Plague from flea bites or bitten directly by the ground squirrel.             Here is some very good information on ground squirrels from the University of California Ground squirrels

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Nectarine Fruit and Dried Droplets of Sap

Q. I have an Independence nectarine tree which I have been nurturing for two years. This is the first year I have had fruit! On the fruits I kept I am seeing something that looks like dried droplets of sap coming out of the skin. It is not sticky to the touch. Are you able to determine if I have some sort of blight with the fruit? Will I just need to take this plant out? A. Your nectarine fruit has damage caused by Western Flower Thrips. This is a very common problem with nectarine fruit here in the valley and elsewhere. Once you see your fruit damaged by this insect, you will see it in future years as well. Be prepared to spray.             Damage to the fruit starts before they are the size of a pea. The only control is to apply sprays to the fruit and leaves to protect the fruit from thrips damage. The most effective sprays are insecticides for organic production contain Spinosad in the list of ingredients. Follow the label precisely. Readers nectarine fruit with dried sap due to thrips damage             If you don’t mind applying an effective conventional insecticide, then look for one containing synthetic pyrethrins, sometimes called pyrethroids. The label must say it is approved for tree fruits. Again, it is very important to read and follow the label for best results.             These sprays must be applied to the fruit and leaves starting very early in the season when the fruit are still very, very small. Sprays must be repeated through the season for total protection. Chances are, you will still see some scarring of the fruit but it will be greatly improved.

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Tops Dying Back in Japanese Blueberry

Q. I’m having a problem with my Japanese blueberry trees. Some are fine but the two on the end appear to be drying out from the top down.  Do you have any idea what’s causing this? The soil is not dry and they all get the same amount of irrigation. A. The usual problem in damage or death to the top of a tree can be found on the main trunk just below the damaged area. I am guessing something has damaged the tree at that point.             The reason for the damage could be several. Borers cause mechanical damage to the trunk and shut off the water going to the top. Diseases in this same location can do exactly the same thing.             Because Japanese blueberry is relatively thin barked, sunburn from our intense sunlight can kill the trunk in that location and shut off water to the top. Humans can cause damage to the trunk and shut off its water supply as well. Top of dead stem on readers Japanese blueberry             I think we can rule out pathological diseases in our climate. The two most likely culprits are mechanical damage to the trunk by borers or the same type of damage caused by sunburn.             Inspect the trunk at the location just above the healthy area of the canopy. Use your fingers and see if you can pull away any loose bark. Borers tunnel just under the bark usually on the side towards the most sunlight. This kills that part of the trunk and the bark peels away easily.             If you don’t see bark peeling from the trunk at this location, look for discoloration of the trunk on this side facing the sun. Sunburn to the trunk can happen in one hour of intense sunlight during the midday or late afternoon.             If it is borers there is nothing you can do to raise the dead area back to life but you can protect the tree from extensive borer damage with an insecticide soil drench once a year.             In any case, you’ll be forced to remove the dead top from the tree with a pruning shears or saw this winter. Once you do this, it may open remaining branches for sunburn as well. Give them as much protection as you can.             I would not do it now because the sunlight is too intense and will probably cause even more damage to the lower, healthier part of the tree.

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Pepper Brown Spots Could Be Irrigation or Sun

Q. I have a brown area on the bottom of my bell peppers. Any ideas? A. Brown spots on bell peppers are normally from either of two things; a disorder we frequently see on tomatoes called blossom end rot or sunburn.             If it is on the bottom of the fruit and not in a spot exposed to direct sunlight it is most likely blossom end rot of pepper. Blossom end rot, just like in tomatoes, is normally associated with irregular watering even though it is a nutrient deficiency.             An inch of mulch in the vegetable bed helps to maintain more even soil moisture and less fluctuating of the water content in the plant. A more even soil moisture content has been reported to reduce the incidence of blossom end rot. Blossom end rot bell pepper             The other possibility is sunburn. If the brown spot is on the shoulder of the fruit toward the sun and not the blossom end, then it is most likely sunburn. This is because there is not enough shade covering the fruit. You will see less sunburn on peppers that are buried deeper inside the canopy of the plant.             With bell peppers in particular we want as much leaf cover over the fruit as possible. Light shade, about 30%, over the plants, also reduces sunburn. Mulching the vegetable garden also helps.             Having the garden in a location where it is exposed to morning and early afternoon sun, with shade during the late afternoon, will also reduce the problem.

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Calling All Las Vegas Gardening Bloggers and Social Media Types!

Social media types and those who have been thinking about getting started and need a little help. Please RSVP to me at [email protected] so I have an idea about how many might be coming. I have been wanting to meet bloggers and other social media types in the Las Vegas area for quite awhile. My idea was to get together, socialize, share some ideas and help promote each other. I have a meeting already scheduled at Viragrow in North Las Vegas on Saturday, June 21,and I would like to specifically invite you as well. I would suggest a very open agenda: Introductions Brainstorming of ideas. Resolution of ideas. Adjourn.   Viragrow is located at 1100 East Dehli St. near Cheyenne Exit of I15 and Losee Road in North Las Vegas. Exit on Cheyenne and drive West toward Losee Road. Turn right or north on Losee approximately 150 yards to the first traffic light which is Colton. Turn left or west on Colton a distance of 20 yards and take an immediate or first right on Bruce. Travel north on Bruce about two blocks and Delhi St is on your left or west. Viragrow is about 50 yards west on Delhi St. It is best to park outside the fence next to the road due to truck traffic into and out of the yard.   A map can be found here. http://www.viragrow.com/directions

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Horticulture/Gardening Meeting Saturday Morning June 21 Las Vegas

This is an exploratory social get-together for interested desert gardeners, horticulture and social media types in the Las Vegas area. I am proposing a 9 am meeting at the Viragrow meeting room on Saturday, June 21, for those interested. There will be some healthy and not so healthy refreshments, coffee and tea available.   Please RSVP to me at [email protected] so I have an idea of numbers who might be coming. I would suggest a very open agenda: Introductions Brainstorming of ideas. Resolution of ideas. Adjourn. Viragrow is located at 1100 East Dehli St. near Cheyenne Exit of I15 and Losee Road in North Las Vegas. Exit on Cheyenne and drive West toward Losee Road. Turn right or north on Losee approximately 150 yards to the first traffic light which is Colton. Turn left or west on Colton a distance of 20 yards and take an immediate or first right on Bruce. Travel north on Bruce about two blocks and Delhi St is on your left or west. Viragrow is about 50 yards west on Delhi St. It is best to park outside the fence next to the road due to truck traffic into and out of the yard.   A map can be found here. http://www.viragrow.com/directions

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Importance of Surface Mulch for Vegetables

Surface mulches are under appreciated when growing shallow rooted vegetables during the heat in hot, desert or arid climates. Learn why. Using mulches when growing vegetables can be very important in hot, dry climates. Garden soils dry quickly and a surface layer of mulch helps keep the soil cooler and retains soil moisture much better than a loose, uncovered garden soil. This can be particularly beneficial to shallow rooted vegetables such as onion, garlic and other root crops.  Try to use light colored mulches like this bedding in the summer months to help reflect energy from the sun and keep it from heating up the soil. In the winter time when the air temperatures are much cooler, use dark colored mulches to help warm the soil and speed germination. Mulches help keep the soil cooler, retain moisture and suppress weed seed germination. Organic mulches which decompose help add structure to desert soils.  The problem has been what to use and cost. In the past I have used clean, bailed straw but it is expensive and doesn’t decompose rapidly when it is fresh. You can turn it under after harvest and it will decompose but it decomposes rather slowly. I tried using wood shavings like you can use for horse bedding. It works well as you can see from this picture of onions that were mulched versus onions that were not mulched in front of them. The horse bedding can be turned under easily after harvest and decomposes rapidly in moist soils. I was pretty impressed with it and it’s cheap. I got the horse bedding in 3 1/2 cubic foot bags from Viragrow in Las Vegas for $4. I am sure you can find it other places as well. I put down about half an inch of horse bedding on top of the soil in April before the heat and it made a big difference. If you are going to seed in the heat, I would highly recommend mulching the surface with something like this. You can also take the time to shred newspaper and it will do about the same thing. A big problem starting plants from seed in the garden during the heat is the soil drying too quickly and the see failing to germinate or germinating very slowly.

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