COOP - Extension FAQs

Box Elder bugs have emerged already and are breeding. They get into the house and crawl all over the west facing exterior house wallsand are all over the vegetable garden beds. How do I erradicate them?

erin@biology.usu.edu (Erin Hodgson) — Mon, 14 Apr 2008 00:00:00 MST

Boxelder Bug Management.

Please read over our fact sheet for more information . In general, they are very difficult (if not impossible) to eradicate. Boxelder bugs are considered nuisance pests, but sometimes they can damage fruit. Mostly they accidentally move into homes for warmth during the winter and that’s when they really become a bother.

We have a 9 acre cabin site in the conifers near Soldiers Summit at 8400 ft. In recent update on google earth I noted new blighted red area in tree tops. Who are professional applicators or can land owner administer insecticide? Arborjet recommends several treatments see www.arborjet.com/problems-solutions/pine-bark-beetle.htm

maggies@ext.usu.edu (Maggie Shao) — Mon, 14 Apr 2008 00:00:00 MST

I suppose my experience in forestry is why I was forwarded your question about conifers on 9 acres near Soldiers Summit. From Utah Division of Forestry, Fire & State Lands Forest Health 2003 report, Mixed conifer forests occur at elevations from about 8,000 to 10,000 feet. Douglas-fir, white fir, and lodgepole pine are the main tree species in this type. Spruce, subalpine fir, and ponderosa pine may also be a component of mixed conifer forests. Species diversity in this habitat type contributes to wildlife habitat diversity.

Bark Beetle Impacts

In a healthy forest, endemic levels of insects and diseases serve to remove weakened and stressed trees, thus thinning the forest and reducing competition for light, water, and nutrients. Overly dense forests composed primarily of larger diameter mature trees are less vigorous. Such sites are preferred by many species of bark beetles, which contributes to outbreaks. Large-scale insect outbreaks often result in an accumulation of down woody debris,which can increase fire intensity.

Before spraying, it is of utmost importance to have proper diagnosis of tree health. We have been in a drought for 7-8 years in the last 10 years, so browning of needles does not necessarily mean there is a pest issue. Granted due to drought stress, trees do become more susceptible to secondary health issues like beetle infestation or plant diseases. Here are a couple links to Utah Division of Forestry, Fire & State Lands information on bark beetles in Utah.

Ips Bark Beetle

http://www.ffsl.utah.gov/foresthealth/insectdisease/IpsengraverBeetle.pdf

Mountain Pine Beetle

http://www.ffsl.utah.gov/foresthealth/insectdisease/Mountainpinebeetle.pdf

There are recommendations on the fact sheet, again only after a proper diagnosis from a forester or arborist to confirm.

When is the proper time for me to spray for worms on my Bing Cherry Tree? What do I use?

jaydee.gunnell@usu.edu (Jaydee Gunnell) — Wed, 02 Apr 2008 00:00:00 MST

To control the worms in cherries there are a few techniques to determine when to spray. The first is based on fruit color. The small Western Cherry Fruit fly cannot effectively insert an egg into the fruit until it starts to change color from straw-color to a rose blush. Utah State University traps and monitors orchard pests throughout the growing season. Updates regarding determining spray time along with products can be found on the USU Extension website: http://www.utahpests.usu.edu. Some common products include; Spinosad, permethrin, carbaryl, and malathion. Be sure to always follow the label instructions when using chemicals.

I have an infestation of red ants in my retaining wall area where I also have plants. What is the best way to get rid of the red ants so I can weed etc. in that area?

ryan.davis@biology.usu.edu (Ryan Davis) — Mon, 31 Mar 2008 00:00:00 MST

The answer to this question is not so straight forward, and really depends on the type of ant. Some ants have more than one queen, one or many satellite colonies, create new colonies by various methods, while some are of concern and others are not.

You can see that if a colony has more than one queen or many satellite colonies it might take more than a soil drench to
kill off the ants. It would be ideal to have some samples of worker ants sent in for me to identify so we can properly treat the ants. And, by the way, just because these ants are red doesn't mean that they are imported red fire ants, we do not have those in Utah; a lot of ants are small and red.

If you are looking for a quick fix you can try to use pesticide ant baits. Because ants share food within the nest, they will spread the pesticide around to each other (and hopefully 1 or all queens). These are not fast-acting because they are purposefully formulated to take a while to kill giving the ants time to pass it around the nest. That said, depending on the ant species baits may not be effective. A soil drench of something like ALLECTUS G INSECTICIDE which will target adult ants AND larvae might work, but the whole subterranean colony would have to be soaked. Spraying worker ants will do nothing to alleviate the problem. The queen(s), eggs and larvae must be killed. If main colonies are treated and satellite colonies exist, then the area will become re-infested.

In summary, I really need to ID the ants before a management strategy can be formulated.

This is probably not the answer you were looking for, but ants are difficult to control when you know which species you are treating, let alone having no idea. If you can get samples to send in it would really help. (collecting as many ants as you can would be best). And be careful...some ants sting, some bite, some bite and spray formic acid on the wound and some do nothing.

I was told there was a worm that eats the goathead or Tribulus Terrestris is that true?

ewevans@biology.usu.edu (Edward Evans) — Wed, 19 Mar 2008 00:00:00 MST

Yes, there are two insect species that eat puncturevine (Tribulus terrestris) and that have been distributed widely throughout western North America as biological control agents. They are two species of weevils of the genus Microlarinus, and their immature stages are "worm-like". They are thought to have reduced numbers of puncturevine significantly in California. They have been introduced repeatedly to Utah over the years, but without lasting success. Apparently our climate is too cold during the winter for them.

We have been putting the dog poop in the composte pile. Is this going to be bad for our composte or for our garden?

shawno@ext.usu.edu (Shawn Olsen) — Wed, 19 Mar 2008 00:00:00 MST

It is recommended that dog and cat manure and litter not be added to compost piles because these materials may contain parasites or pathogens which are harmful to people. These pathogens are not always killed by the heat of the compost pile. Also, dog and cat manure may attract unwanted dogs and cats to the compost pile. You can safely add horse, cow, and poultry manure to compost piles.

Shawn Olsen

Davis County Office

Utah State University Extension

Can you please give me an idea of when I need to spray my fruit trees (I have one each of nectarine, peach, apricot, apple and cherry).Can you let me know when, based on the weather in Cache county? What is the name of the best spray to use?

taun.beddes@usu.edu (Taun Beddes) — Wed, 19 Mar 2008 00:00:00 MST

Unfortunately there is not a magic spray that can be sprayed on all fruit trees, with the exception of dormant oil. This should be sprayed within the next couple of weeks to help control aphids, scale, and other pest and some diseases. Do not apply it once trees have leafed out or you have had problems with shothole fungus (Coryneum Blight) that also needs to be treated with an appropriate fungicide. Captan is labeled for this. The following hyperlink will lead to a Website that provides info on when to spray or trap insect pests http://utahpests.usu.edu/ipm/htm/advisories/treefruit. You may subscribe to the Website for regular updates on current insect and disease sightings and outbreak predictions, and highlights upcoming concerns for tree fruit growers. A traditional pesticide good for controlling coddling moth on apples is Sevin (carbaryl). For trees such as cherries and peaches Malathion can be used if needed. Consider using alternatives more sustainable to these including traps and baits. The Utah plant pest diagnostic lab has more specific info on this http://utahpests.usu.edu/.

I want to put pre emergent down on my garden to control weeds and the tomato seeds from last year. The snow has melted. Is now the time and what should I use?

dand@ext.usu.edu (Dan Drost) — Wed, 19 Mar 2008 00:00:00 MST

One of the problems we have with using pre-emergence herbicides in the garden is that they may affect some of the vegetables we grow. In addition, don’t expect to control all weeds in a garden of mixed vegetables with one herbicide. Why? First, no single herbicide controls all weeds. Secondly, some vegetables are also sensitive to the herbicide, and if the wrong herbicide is used, the vegetable is injured along with the weeds. Finally, some herbicides have quite long residual activity and may have a long-term negative effect on subsequent garden plants.

Generally it is recommended that a gardener use a combination of hand weeding, cultivation, mulching and good garden hygiene to keep weeds under control. Most of us know what hand weeding involves. Cultivation can include tilling, hoeing, and mowing. Several types of mulches used in the garden include plastics, weed barriers, grass or straw mulches, or newspaper or cardboard. Garden hygiene means that we don't allow annual weed to produce seeds that build up the weed problem.

If you do decide to use a herbicide, here are a couple of suggestions. Remember, they need to be applied at the appropriate dosage, at the correct time relative to the weeds you are trying to control, they may need incorporation into the soil, and may only control some of the weeds in a garden

Dacthal (several brand names available) can be used on a wide variety of vegetable plants. Applied correctly, Dacthal gives good control of most grass weeds and a few broadleaf weeds. Dacthal controls weeds as the seeds germinate, so remove existing weed plants prior to application.

Trifluralin (several brand names available) is a pre-emergence herbicide used to control grass problems in the garden. Treflan should only be applied to vegetable tolerant to this herbicide. For the best weed control, mix Treflan with garden soil. After application, mix the herbicide in the top 2 inches of the soil. Read the package label for a list of approved vegetables.

Poast is a post-emergence herbicide that selectively controls grass weeds in several vegetables. Apply Poast to the grasses before they reach 8 inches tall. Mix a crop oil concentrate in the spray solution before application. Read the Poast label for specific instructions and approved vegetable crops.

Glyphosate (several brand names available) is a nonselective, post-emergence herbicide approved for limited use in the vegetable garden sites. Glyphosate is used to eliminating existing weeds before a vegetable seedling emerges from the soil and before vegetable plants are transplanted in the garden. Read the label for specific application instructions and limitations.

For more detailed information on weed control for the yard and garden, refer to the Utah State University extension fact sheet "LANDSCAPE AND GARDEN WEED CONTROL" http://extension.usu.edu/files/publications/publication/HG508.pdf

I have a curly willow that was topped about four years ago. Now it needs to be trimmed. Can I cut the branches back to where they were cut last?

jaydee.gunnell@usu.edu (Jaydee Gunnell) — Wed, 19 Mar 2008 00:00:00 MST

Topping or hat-racking are two pruning practices that are not recommended, precisely because of what you have described. The new growth is extremely vigorous and tends to grow straight up in the air or at very weak angles. These “water sprouts” shade the interior of the tree and are typically not structurally sound and may be easily broken in high winds or snow loads. Repairing a tree that has been cut in this manner is difficult. To keep cutting the water sprouts down to the original point of topping will just re-create the problem in years to come. It may pay to hire a certified arborist to come out and evaluate the trees all around health. You can find information on certified arborists at, http://www.utahurbanforest.org/certified.html.

I live in Lindon and have heavy clay soil. I have been adding leaves and grass to my garden soil and it still compacts rapidly. Can I use the compost from the green and public waste dept. on a vegetable garden?

juliat.ucadm.utahcounty@state.ut.us (Julia Tuck) — Mon, 03 Mar 2008 00:00:00 MST

"Green Waste" such as leaf and branch compost is wonderful for your vegetable garden. Be sure and incorporate it into your soil. Most vegetables can grow roots down 15" but tomatoes can go down 18" so give the garden a good 18" base in which to grow.

Since you have heavy clay soil, it would be helpful if you changed to raised beds (Grow Box Gardening). They would dry out quicker in the spring and give good drainage during the season. Make your beds no wider than 4' deep (you can reach and harvest 2' from one side and 2' from the other side and not have to step in the garden to harvest the produce). I would leave 18" to 2' between the rows so that you can walk down the rows and harvest your vegetables without stepping on the plants.

-Julia B. Tuck
Horticulture Assistant
Slow the Flow Schedule Coordinator
USU Cooperative Extension
Utah County

I have a lawn with necrotic ring, it has been treated with f:stop. Question; Future construction will remove much of the sod. Should I treat the soil before I lay new sod.

kelly.kopp@usu.edu (Kelly Kopp) — Thu, 24 Jan 2008 00:00:00 MST

I would not recommend treating the soil prior to laying new sod. While you have experienced problems with necrotic ring spot, the organisms that cause
this disease are always present. They only "outbreak" when the conditions are right. What I would recommend is that you work to keep the new sod
healthy and manage it so that outbreaks of necrotic ringspot are reduced.

To that end, cultural controls recommended by our Plant Pest Diagnostic Lab include:

Cultural techniques that prevent the lawn from becoming stressed will help prevent these two diseases. In early spring or fall, the lawn should be
aerated. Aeration improves water penetration and reduces thatch, thus alleviating conditions that cause stress. Nitrogen fertilizer should be
applied frequently at low rates or in slow release forms such as sulfur coated urea or IBDU. This avoids undesirable flushes of growth which are
more susceptible to disease. Mow the lawn at a height of 2-3 inches often enough so that only 30-40% of the leaf length is removed per mowing. In most
soils, the lawn should be watered infrequently and deeply. Sandy soils will require more frequent, light irrigation. Wet the entire rot zone when
irrigating.

I've neglected to do my "last mow" up to this point. We've already had several nights of light frost. My grass is long but I worry about causing even more damage by mowing at this late juncture, mid-November. Are there any risks to mowing grass after the first few frosts?

kelly.kopp@usu.edu (Kelly Kopp) — Thu, 15 Nov 2007 00:00:00 MST

In response to your mowing question, you should still be fine to do that"last mowing" but do it SOON! You are correct in that leaving it long would be worse.

What is the proper time to fertilize fruit trees? Also, is there only one appropriate time of year to prune fruit trees?

maggiew@ext.usu.edu (Maggie Wolf) — Fri, 19 Oct 2007 00:00:00 MST

Spring and early summer are the times of year most commonly recommended
for fertilizing. Most of the time, most trees only need nitrogen. A soil
analysis will tell you if phosphorous or potassium should be added. The
general rule of thumb is to apply one-eighth to one-quarter pound actual
nitrogen per year for every inch of trunk diameter. So, a tree with a trunk
about 2 inches wide (diameter at breast height)should get about 10 ounces
(five-eighths pound)of ammonium sulfate every year. You could apply this in
spring only or you could split the amount into two applications - one in
early spring just as buds break and again in early summer.

The best time to prune is in spring before the tree leaves dormancy but
after the coldest part of winter is past. However, it's better to prune late
than never at all, up until July. Past then, you should do only very minimal
pruning or none at all, to avoid prompting re-sprouting that will deplete
the tree's energy reserves before it goes dormant again.

I have many large 20-25 feet scrub oak trees on my property. I would like to thin and prune them from the tops in order for them to look like the lower scrub oak I have seen in the area, about 10-15 feet. How low can I cut them from their tops without injuring them and what is the best time of year to do so?

heidi.wayman@usu.edu (Heidi Wayman) — Wed, 17 Oct 2007 00:00:00 MST

The best way to prune a tree that has grown out of its space and is too tall is to use a method called crown reduction or drop crotch pruning. This method is preferred over topping or pollarding because it is healthier for the tree and the tree keeps a more natural appearance. When making the pruning cuts you want to cut back to lateral branches that are at least 1/3 of the diameter of the limb that is being removed. Once you have identified which branches you want to remove you will want to follow these steps:

With the first cut, make a notch on the side of the stem away from the branch to be retained, well above the branch crotch.

Begin the second cut inside the branch crotch, staying well above the branch bark ridge, and cut through the stem above the notch.
Cut the remaining stub just inside the branch bark ridge through the stem parallel to the branch bark ridge.

This method of pruning will help make sure that you do not damage stem tissue when removing the branch. As with all types of pruning you want to avoid flush cuts, cutting the branch off flush with the trunk and stub cuts, leaving a short stub of the branch on the tree. Both flush cuts and stubs can contribute to increased stress and disease in your trees.

For most trees the best time to prune is when they are dormant. Fall is the most common time to prune trees. Pruning trees during this time will allow you to see the structure of the tree and help you decide where you will make pruning cuts. This will also reduce the chance of spreading diseases and excessive sap flow.

You can find more information, including illustrations of proper cuts and definitions of pruning terms, by following this link to the USDA Forest Service guide on how to prune trees. http://www.na.fs.fed.us/spfo/pubs/howtos/ht_prune/htprune.pdf

Why is the timing of dormant spray important?

juliat.ucadm.utahcounty@state.ut.us (Julia Tuck) — Mon, 15 Oct 2007 00:00:00 MST

Using a delayed dormant oil is an effective control for several small pests, such as aphids, mites and scale. You want to apply the spray before the blossoms open so that you kill the eggs before they hatch as the temperature gets warmer. Also, if you wait until after the blossoms open, and if you have included an insecticide with the oil, you could seriously hurt or kill the pollinators that come to pollinate the flowers. If you spray when the blossoms are open, the oil may damage the blossoms and prevent fertilization of the flower which could diminish your fruit production.

I hope this information will be of help to you

I have two new flowering pear trees that are being used as breakfast, lunch and dinner. I am not sure what is eating them the leaves have large scallops taken out of them. The lower branches have been affected more than the top ones. Any ideas?

heidi.wayman@usu.edu (Heidi Wayman) — Mon, 15 Oct 2007 00:00:00 MST

Without actually seeing the damage to your leaves it is difficult to give you an accurate diagnosis of what is happening. By your description there may be two different types of insects causing the notches in your pear tree leaves. Properly identifying what is causing the damage can help you decide on what control methods to use.

The first type of insect that causes damage like you described is a root weevil. Two common varieties that could be damaging your pear trees are Lilac Root Weevil (Otiorhynchus meridionalis) and Strawberry Root Weevil (Otiorhynchus ovatus). These insects are particularly hard to find on your plants because the adults hide during the day, only feeding at night and the larvae live in the root zone of the plant feeding on the tissues there. Because they can be difficult to find you could create a trap by placing a fold of burlap around the base of the tree or by burying a paper cup at soil level. This will allow you to collect a specimen. If it is root weevils a non-chemical method of control would be the use of commercial sticky traps placed in a protected area either in or near the tree. If you choose to use a chemical insecticide use one that is a Pyrethroid. The following link has more information on root weevils http://www.ext.colostate.edu/pubs/insect/05551.html

The second type of insect that may be causing the damage is Leafcutter bees. They are a native species of pollinators that use the portion of the leaf that they have notched out in rearing their young. These insects are not pests and control practices are not recommended because they are very beneficial in helping to pollinate our crops and ornamental plants.

By following this link you can see pictures that show what typical damage of both Root Weevil and Leafcutter Bees looks like.

http://utahpests.usu.edu/ipm/files/uploads/HortAdvisories/2007/Hort-IPM-06-27-07.pdf

To help provide you with a better diagnosis of what is happening to your pear tree leaves you can bring a sample into the USU Extension Office located at 2001 S. State Street for identification. Our office hours are Monday through Friday 8:00 am to 5:00 pm.

Precautionary Statement: All pesticides have benefits and risks, however following the label will maximize the benefits and reduce risks. Pay attention to the directions for use and follow precautionary statements. Pesticide labels are considered legal documents containing instructions and limitations. Inconsistent use of the product or disregarding the label is a violation of both federal and state laws. The pesticide applicator is legally responsible for proper use.

I have rings in my lawn that are about two feet wide. I suspect they are fairy ring, but the description for fairy ring doesn't quite fit. The inside of the circle is not lush and green, it looks the same as the rest of the lawn. There is just a semi-dead cirle surrounding good lawn. Do you have any help for me.

heidi.wayman@usu.edu (Heidi Wayman) — Fri, 12 Oct 2007 00:00:00 MST

Without actually seeing your lawn it is difficult to give you an accurate diagnosis of your problem. There are several reasons that your lawn may have brown spots or rings. The most common culprit is water. If you have a sprinkler head that is blocked, missing, or broken it can cause some parts of your lawn to become brown. A check of your sprinkler system can help you to identify if this is the problem. You can find a once a month sprinkler system checklist at http://www.conservewater.utah.gov/OutdoorUse/MaintenanceCheck.htm.

Another reason you may be seeing brown rings in your lawn may be insect related. Before applying any pesticides it is very important to identify what kind of insect it is. The best way to diagnose an insect problem is to check the lawn. Insects typically feed on the edges of the brown spots. If you do find an insect but are unsure of what kind of insect it is the Utah Pests Webpage http://utahpests.usu.edu/ has a lot of information including pictures. You can also bring a sample of the insect into the USU Extension Office located at 2001 S. State Street for identification. Our office hours are Monday through Friday 8:00 am to 5:00 pm.

A third reason may be a fungal disease. There are two different diseases that match your description. The first is Necrotic Ring Spot. This is a cool season disease that shows up March through May and September through November. This particular disease is very common in 2 to 5 year old bluegrass lawns that have been established from sod. It shows up as dead circles or arches of browning lawn that range in size from a few inches to a few feet that are surrounded by a patch of green lawn that gives a donut appearance. The second disease is called Summer Patch. It has very similar symptoms as Necrotic Ring Spot. It becomes evident May through September. Some recommendations in treatment for fungal diseases are:

1) Control thatch buildup with regular core aeration at least once a year.
2) Water less frequently but to greater depth. The soil should be moistened 8 – 10 inches deep.
3) Remove layers of leaves from lawn during winter.

You can learn more about these turf diseases at http://utahpests.usu.edu/plantdiseases/htm/turf/turfdiseases.

To help provide you with a better diagnosis of what is happening in your lawn and a better treatment plan you can bring a sample into the USU Extension Office. To take your sample, dig a 4- to 6-inch chunk of lawn (including the soil) on the margin of a brown spot. Include a section with both living and dead turf.

When is the proper time to apply dormant spray? And If I use dormant spray do I still need to spray later in the season. I have apples, pears, peaches, apricots. Also will dormant spray help with the Japanese beetle?

juliat.ucadm.utahcounty@state.ut.us (Julia Tuck) — Thu, 11 Oct 2007 00:00:00 MST

The spray that is
applied to the fruit trees is actually a "Delayed Dormant Oil." We have
a sheet in the office that shows at what bud stage to apply the delayed
dormant oil. It has pictures of each of the types of fruits trees and
shows the right time to apply it. If you send me your address, I will
be happy to send you a copy.

For general information:
The delayed dormant oil is a wonderful step in Integrated Pest
Management. It will kill both the eggs and adults of aphids, mites,
peach twig borer, pear psylla, scale insects and leafrollers before
they can cause problems. They also can't get resistance to it- they
can't say "this time I'll smother, next time I won't."

Apples: apply the delayed dormant spray at first sign of green on
bud tips to ½" green stage (about 2-3 weeks before bloom)
for coddling moth, apply the delayed dormant spray
starting 10 days after petal fall. Reapply sprays based on protection
interval through the first week of

September

Pears: for coddling moth, apply the delayed dormant spray starting
10 days after petal fall. Reapply sprays based on protection interval
through the first week of
September

Peaches, Nectarines, and Plums- apply the delayed dormant oil from
first bud swell to first pink (peach) or green tip (plum)

Cherries: apply delayed dormant spray at bud swell to green tip

Apricots: apply delayed dormant spray from separation of bud scales to
first sign of white in bud tips

There is an excellent booklet that we sell at the office that you can
access for free online. It is called the Home Orchard Pest Management
Guide. It is published by Utah State University. To view this
information, go to:

http://extension.usu.edu/files/publications/HomeOrchardGuide2004.pdf

You can use "horticulture oil" or "volck" oil. The difference between
the spring delayed dormant oil, and the fall dormant spray, is the
amount of oil used. The directtions should be on the label for both
formulations.

Our 4 year old peach tree is blossoming and we noticed a "web" full of caterpillars in one of the branch forks. Several of the 1/2 to 3/4 inch larvae were on other branches as well. EEWWW! What do I do?

maggiew@ext.usu.edu (Maggie Wolf) — Fri, 05 Oct 2007 00:00:00 MST

I suspect you are seeing the boxelder leafroller, but you would need to bring some to your county Extension office to have a proper diagnosis and identification.

Read about the boxelder leafroller by downloading the USU Extension publication "Boxelder Leafroller", from http://extension.usu.edu/files/publications/factsheet/29.pdf

We have scrub oak in our back yard. Almost overnight we have thousands of little green worms that have made webs over the leaves of the trees and are eating every green leaf in sight! Help! What do we do???

maggiew@ext.usu.edu (Maggie Wolf) — Fri, 05 Oct 2007 00:00:00 MST

I suspect you are seeing the boxelder leafroller, but you would need to bring some to your county Extension office to have a proper diagnosis and identification.

Read about the boxelder leafroller by downloading the USU Extension publication "Boxelder Leafroller", from http://extension.usu.edu/files/publications/factsheet/29.pdf