Landscape & Garden Alerts

Powdery Mildew Outbreak

Landscape and Garden    Treasure Valley

Powdery Mildew

Posted on: September 6, 2018 by Maria Held

Powdery mildew has been observed on squash, zucchini and carrots. It affects almost any type of plant including ornamentals such as peony, lupine and pansies.
Powdery mildews are characterized by spots or patches of white to grayish, talcum-powder-like growth.
It grows readily in our warm and dry climate. When available choose resistant or tolerant varieties. The disease is common in crowded plantings where air circulation is poor and in damp, shaded areas. Avoid overhead irrigation and late summer application of nitrogen fertilizer once symptoms occur. Remove and destroy all infected plant parts (leaves, etc.). Do not compost infected plant debris. Temperatures often are not hot enough to kill the fungus.
Chemicals are most effective when combined with cultural controls.

» http://extension.colostate.edu/topic-areas/yard-garden/powdery-mildews-2-902/

» http://ipm.ucanr.edu/PMG/PESTNOTES/pn7406.html

» http://ipm.ucanr.edu/PMG/PESTNOTES/pn7493.html

Sunscald in peppers and tomatoes

Landscape and Garden    Treasure Valley - Idaho

Posted on: August 20, 2018 by Maria Held

Due to high sun exposure on peppers the fruit may develop areas that go from green to yellow and sunken, then become dry and brown. In the case of cucumbers the green bleaches out to white and the tissue becomes soft. Because of extreme temperatures this is occurring more than usual this season. Sufficient leaf cover is the best prevention. Shading the affected plants especially on the west side with shade cloth is helpful.

» http://msue.anr.msu.edu/news/hot_and_sunny_days_promote_sunscald_in_peppers_and_other_vegetables

» http://ipm.illinois.edu/diseases/series900/rpd939/rpd939.html

» https://extension.illinois.edu/vegproblems/sunburn.cfm

Herbicide Damage to non target plants.

Landscape and Garden    All Locations

Herbicide damage

Posted on: July 3, 2018 by Rich Guggenheim

We are seeing considerable damage to plants consistent with broad leaf herbicides being misapplied. Always read and follow all label instructions. It is against the law to use pesticides in a manner inconsistent with label instructions.
Click the links below to learn how to diagnose and prevent herbicide damage.

» https://www.extension.purdue.edu/extmedia/id/id_184_w.pdf

» https://hnr.k-state.edu/extension/info-center/common-pest-problems/common-pest-problem-new/Herbicide%20Damage%20to%20Trees%20Shrubs%20Turf%20and%20Garden%20Plants.pdf

» http://herbicidesymptoms.ipm.ucanr.edu/HerbicideDamage/

» https://hortnews.extension.iastate.edu/2018/06/preventing-herbicide-injury-landscape

Curly Top Virus in Solanacea Plants

Landscape and Garden    All Locations

BCTV

Posted on: July 2, 2018 by Rich Guggenheim

BCTV affects Beets, tomatoes, peppers, beans, potatoes, spinach, cucurbits, many ornamentals, and weeds such as Russian thistle (tumbleweed) and mustard. It is spread by the Beet leafhopper (Circulifer tenellus). There are no chemicals available for controlling the virus. Management foci include:
Plant virus-free transplants
Control weeds and insects
Remove infected plants
Cage young plants in home gardens. Good sanitation practices, such as weed and insect control, are also essential in limiting the occurrence of the disease. Home gardeners may also consider planting susceptible hosts, such as tomatoes and peppers, in a slightly shaded part of the garden, as leafhoppers prefer to feed in sunny locations

» http://utahpests.usu.edu/uppdl/files-ou/factsheet/curly-top-tomato08.pdf

» http://ipm.ucanr.edu/PMG/r783102011.html

» http://entoweb.okstate.edu/ddd/diseases/curlytop.htm

» http://aces.nmsu.edu/pubs/_h/H106/

Squash Bug confirmed in 2018 squash.

Landscape and Garden    All Locations

Anasa tristis

Posted on: June 30, 2018 by Rich Guggenheim

Squash bugs have been confirmed in the Treasure Valley.
It attacks all cucurbits and vine crops but is most damaging to squashes and pumpkins. The insect has a disagreeable odor when crushed and is one of many insects known by the nickname "stink bug."
They may be difficult to see because their color matches the soil and because they are usually hiding under the vines, leaves or clods of dirt. The adults feed on sap from the plant leaves as they lay clusters of a dozen of more, large, brick-red to yellow-brown eggs on the lower sides of the leaves.
Handpick and discard egg clusters and nymphs as they appear. Use garden insecticides such as Sevin, permethrin or insecticidal soap according to label directions. Sprays are generally more effective than dusts, but must be reapplied frequently. Avoid spraying plants in bloom. If spraying during bloom is necessary, spray at night after honey bees have quit foraging for the day.

» https://extension.usu.edu/juab/ou-files/ENT-120-08.pdf

» http://extension.colostate.edu/topic-areas/insects/squash-bug-management-in-home-gardens-5-609/

» http://ipm.ucanr.edu/PMG/PESTNOTES/pn74144.html

» https://extension.usu.edu/news_sections/agriculture_and_natural_resources/control_squash_bugs_with_water

Peach Tree Borer 2018

Landscape and Garden    All Locations

Peach Tree Borer

Posted on: June 29, 2018 by Dian Roberson

We have been finding Peach Tree Borers in our traps! They will attack peach, cherry, plum, and other stone fruits. It is the larva that does the most damage, feeding on the tree roots. Check out the information below!

» https://pnwhandbooks.org/insect/tree-fruit/peach-nectarine/peach-nectarine-peachtree-borer

» http://extension.colostate.edu/topic-areas/insects/peach-tree-borer-5-566/

Scale on Honeylocust (Nampa)

Landscape and Garden    All Locations

Pulvinaria innumerabilis

Posted on: May 30, 2018 by Rich Guggenheim

Cottony maple scale occasionally builds up in large numbers on branches and leaves of honeylocust, becoming quite conspicuous as egg sacs swell in June and July. The overwintering stage of this scale (mated female) can be controlled with dormant oil applications made before new growth in spring. These treatments also can help suppress spider mites, eriophyid mites and plant bugs that overwinter on trees.

Newly hatched crawlers generally appear in late June through July and can be controlled at that time with Sevin, Orthene or various pyrethroids. Imidacloprid (Merit) applied as a soil systemic treatment should also be effective, provided sites are irrigated. Natural controls generally maintain cottony maple scale at nondamaging levels and sustained infestations lasting more than one season are very rare.

» http://ipm.ucanr.edu/PMG/PESTNOTES/pn7408.html

» http://extension.colostate.edu/topic-areas/insects/insect-and-mite-pests-of-honeylocust-5-571/

» http://ipm.ucanr.edu/PMG/PESTNOTES/pn7410.html

» https://utahpests.usu.edu/uppdl/files-ou/factsheet/Soft%20Scales%20in%20Utah.pdf

Western Cherry Fruit Fly 2018

Cherry    Treasure Valley

Western Cherry Fruit Fly

Posted on: May 25, 2018 by Paul Castrovillo

On May 22 the first 2018 Western Cherry Fruit Fly captured in an Idaho State Department of Agriculture WCFF trap was reported from Canyon County. Historically we expect to find WCFF in Gem County about a week after the first one is found in Canyon County.

Online phenology and degree-day models for WCFF predict first flight on May 21 in Ontario and Parma, May 24 in Caldwell, May 25 in Emmett, May 29 in Boise and May 31 in Nampa.

If treatment for WCFF is not already underway it should begin now.

For more information contact Paul Castrovillo at paul.castrovillo@isda.idaho.gov or call 208-332-8627.

» https://pnwhandbooks.org/insect/tree-fruit/cherry/cherry-western-cherry-fruit-fly

» http://wci.colostate.edu/Assets/pdf/western.cherry.fruit.fly.pdf

» https://extension.wsu.edu/chelan-douglas/agriculture/treefruit/pestmanagement/cherryfruitfly/

Coddling Moth 2018

Apple    Treasure Valley

Posted on: May 21, 2018 by Dian Roberson

Coddling Moth has been detected in traps so it is time to take action! This is a small moth that lays eggs on the blossom end of Apple and Pear fruit. The larvae them bore into and ruin your fruit. Check out the publications and links below to help you choose the best control for your landscape.

» http://extension.colostate.edu/topic-areas/insects/codling-moth-control-in-home-plantings-5-613/

» https://pnwhandbooks.org/insect/tree-fruit/apple/apple-codling-moth

Pear Blister Mite

Tree Fruits    All Locations

Eriophyes pyri

Posted on: May 9, 2018 by Rich Guggenheim

Pear leaf blister mite, Eriophyes (=Phytoptus) pyri , is an eriophyid mite found on pear, and apple. Young trees can be damaged by severe infestations.
CONTROL:
Treat large infestations in early fall, before leaf drop, when mites are migrating from leaves to buds. Options include carbaryl, horticultural oil, or lime sulfur. Dormant oil applications in spring are also effective. Blister mites cannot be treated in summer.

» http://ipm.ucanr.edu/PMG/r603400511.html

» http://oregonstate.edu/dept/nurspest/pear_leaf_blister_mite.htm

» https://utahpests.usu.edu/ipm/agricultural/fruit/blister-mites

» http://jenny.tfrec.wsu.edu/opm/displaySpecies.php?pn=330

Peach Leaf Curl

Tree Fruits    All Locations

Peach Leaf Curl

Posted on: May 8, 2018 by Rich Guggenheim

Taphrina deformans

Peach leaf curl is affecting peach leaves now. Proper timing of fungicides, in the fall, can prevent this disease aLime sulfur or Ziram work great for commercial growers. Home grown trees will need something but avoid Monterey Liqui-Cop as it did not work. Ortho MAX Garden Disease Control was a little better than nothing. Bottom line for home growing - replace with a resistant tree after the current ones dies.

» https://pnwhandbooks.org/plantdisease/host-disease/peach-prunus-persica-leaf-curl

» http://ipm.ucanr.edu/PMG/PESTNOTES/pn7426.html

» https://extension.usu.edu/files/publications/factsheet/peach-leafcurl.pdf

» http://extension.oregonstate.edu/gardening/node/924

» http://ipm.ucanr.edu/PMG/PESTNOTES/pn7426.html

» https://digitalcommons.usu.edu/cgi/viewcontent.cgi?referer=https://www.google.com/&httpsredir=1&article=1736&context=extension_curall

Peach Tree Borer

Tree Fruits    All Locations

Synanthedon exitiosa

Posted on: May 4, 2018 by Rich Guggenheim

Peach tree borer are in the clear wing moth category. They usually attack prunus trees near the ground. Signs of infestation include gumosis oozing from the trunk near the soil.
Peachtree borer eggs are laid during the summer on the bark at the base of trees. Larvae overwinter in the tree trunk near the soil line. They feed in the crown area and burrow up into the tree

» https://pestadvisories.usu.edu/2017/04/18/gummosis/

» http://extension.colostate.edu/topic-areas/agriculture/cytospora-canker-in-tree-fruit-crops-2-953/

» https://plantpathology.ca.uky.edu/files/ppfs-fr-t-08.pdf

» http://ipm.ucanr.edu/PMG/r5301011.html

Boxelder bugs

Landscape and Garden    All Locations

Box Elder Bugs

Posted on: March 30, 2018 by Rich Guggenheim

Boxelder bugs are active. Management is extremely difficult. Management techniques include:
Exclusion- sealing cracks and around windows, doors, and other entry points.
Eradication of female box elder trees.
Vacuuming- cleaning up the bugs with a shop vac.
Diatomaceous earth can create an effective barrier along with certain contact insecticides. However, repeated insecticide applications have been shown to quickly create resistance and will dramatically reduce natural enemies. Therefore, insecticides should not be used unless necessary to prevent substantial fruit damage. Always read and follow all label instructions.

» https://www.cals.uidaho.edu/edcomm/pdf/CIS/CIS1208.pdf

» http://oregonstate.edu/dept/kbrec/boxelder-bug

» http://www.extension.uidaho.edu/publishing/pdf/CIS/CIS1208-S.pdf

» http://extension.usu.edu/files/factsheets/boxelder.pdf

Clover mites

Landscape and Garden    All Locations

Mites

Posted on: March 20, 2018 by Rich Guggenheim

Spider and clover mites have been confirmed in landscapes throughout Canyon County. They are especially problematic on the south and west facing yards where temperatures are warmer and drier. They can invade homes, where they become a nuisance. Control can be obtained with diatomaceous earth as a barrier. Do not use insecticides to control mites. Always read and follow label instructions.

» http://extension.colostate.edu/docs/pubs/insect/05505.pdf

» https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1877&context=extension_curall

» https://www.extension.umn.edu/garden/insects/find/clover-mites/

» https://www.unce.unr.edu/publications/files/ho/other/fs9605.pdf