Wednesday, June 27, 2012

Squash Bugs They are back!



It does not seem to matter whether the temperatures are 95 degrees fahrenheit or 115 degrees fahrenheit since these pests hide under the base of the plant where it is shaded and cool.  Squash bugs do make their appearance as the warm temperatures of summer begin. 

The aduts are grayish in color.  The top picture is an adult squash bug measuring 11/16 of an inch.  The picture of the underside of the leaf is showing squash bug nymphs which are pale green.  Both suck sap from the stems and leaves.  This feeding leaves injuries which kill and collapse the tissues.  At first, this feeding causes a yellowing on the foliage which later turns brown.  Then the wilts and dies. 

These squash bugs are a member of the leaffooted bug family or Coreidae.  The members are moderate to large sized with a prominent head possessing piercing-sucking mouthparts.  Most of the members have a pronounced flattening of the hind legs. With the exception of the squash bug, most members of this family feed on seeds primarily.   Squash bugs feed on curcurbit crops.

How do you control these pests?  Any pyrethroid insecticide should help control them.  If you do not have pets, then you can place Diatomaceous earth at the base of the plant.  Remove any debris that is under the plants. 

Tuesday, June 19, 2012

Cottonwood Shoot Blight

Description:

If you see new shoots which are blackened and curled to resemble a shepard's crook, these are the signs of shoot blight of cottonwoods, aspens and poplars.  The new leaves will develop irregular brown to black areas before they curl.  After the leaves are affected, then the fungus spreads down the new shoot causing cankers to create the shepard's crook.  The death of these new shoots causes distorted new growth.  Continued annual infections will continue to distort the growth and create a shrubby growth.

The spores of this fungus overwinters in fallen leaves.  Sometimes the spores can be blown in or during extended wet periods secondary infections can reach other parts of the tree because the rain.  High humidity is a favorable condition for this to take hold in limbs below 6 to 8 feet from ground level. 

Control: 

The best control is to rake leaves in the fall away from the cottonwood, aspen or poplar. The uninfected growth becomes more resistant to the disease as the season progresses.  Prune infected shoots in dry, warm weather.  Apply sulfur in wet weather and with temperature < 60 degrees F.



Elm Fungicide

American Liberty Elm, Holyoke, Colorado


For all those with American Elms, you know that in 1983 DuPont Company appointed Elm Research Institute the sole distributor of Elm Fungicide.  This fungicide is said to be 95% effective when used as an annual treatment.  This chemical is the same as Lignasan BLP or methyl 2-benzimidazolecarbamate phosphate.  The Elm Research Institute states that the phosphate portion of this chemical is a source of nutrient for the elms.  They also state that this chemical in non-toxic.


Since 1975, there are over 100,000 American Elms doing well in this country because of annual treatments with Elm Fungicide.  If you recently purchased an American Liberty Elm, the Elm Research Institute recommends that you treat the tree annually. It already is highly resistant to Dutch Elm Disease.  The Institute states this will further insure the tree against infection.  They recommend doing so when the tree reaches a 5 to 6 inch diameter at a one foot distance above ground.  The best time to apply the fungicide is immediately after it leafs out each Spring.

Burlington Community Garden

Come and visit.  Raised beds are a great way to start early and continue late into the season.


Buckets and used tires can also be raised beds.  A great way to recycle.

Here is a way to really conserve water.

Join us.  Contact Linda Langelo at (970)854-3616 at Phillips County Extension.

Wednesday, June 13, 2012

Water is our most precious commodity.

What does water do for us and our plants??? 
 
Water serves as the primary component of photosynthesis and transpiration.  In other words, without water, plants would not take sunlight and make it into sugars and starches and feed themselves.  If plants do not feed themselves, we in turn do not have any food supply, along with our animals and livestock.

Water serves as a solvent to move minerals from the soil to the plant.  Water is the only universal solvent because it dissolves more substances than any liquid.  Water moves chemicals, minerals and nutrients whether in plants or humans or other organisms.

In plants, water is 90% of the weight of a plant.  In humans, water is 60% of a human body's weight.

Can we live without water?  NO.

Can we produce water --- clear, pure water found in nature?  NO.

When environmental drought situations occur, if we cannot live without water and we cannot produce water, then we need to think about conserving water.    Water is the essence of all life.

When extreme droughts occur year after year with no or below average percipitation, then we need to change our thinking about the plants in our landscapes and the crops we grow.  Here are suggestions:

  • Grow plants within their native range.
  • Plant drought tolerant plants
  • Know their water requirements
  • Know their soil requirements
We all have plants that we have that are our favorites.  We want them in our gardens and landscapes knowing their requirements do not match their requirements.  We think we can keep them healthy and alive.  But eventually, they die.  Some will adapt for awhile.  Plants can tolerate a situation for a time. 

Our native environment has its own beauty.  Enhancing that native environment with other plants that need more than what the environment can give, this is a recipe for disaster.  If you are new to Colorado or are looking to make changes in your landscape check out http://plantselect.org.  These plants do not require lots of fertilzer or pesticides or tremendous care.  They are lower maintenance.  Some require supplemental water in extended dry periods.  Some are totally xeric.  You can also find information at Colorado State University Extension Fact Sheets.  There are fact sheets on native plants for the landscape.  These include shrubs, trees and perennials.  Happy plant hunting.  But remember, conserve our water for it is the essence of all life. 

Oak Tatter or Not?

Oak tatter deforms the leaves so that most of the leaf tissue which should be present but isn't.  The leaf tissue becomes very thin along the major veins of the leaves.  The picture above shows a distortion along the major vein in the leaf.  But the leaf is not thin or missing tissue along the major veins.  Pictures above taken by Linda Langelo, CSU Horticulture Program Associate.  Compare to the picture below which is a picture of Oak tatter:

The overall appearance of the crown or top of the tree's limbs will be a lacy appearance.  Pictures from ISU Plant Disease Clinic.

According to Iowa State Universtiy, this disease does not  appear to be related to disease or insect activity, but a physiological deformity caused by adverse environmental circumstances.  The oak tree will recover in time.  This is a foliage problem of recent years.  The problem can happen with low temperatures when buds are developing.  Wind injury can also be a factor at that time.

The final result of the deformity of the first set of pictures is herbicide damage. 

Flea Beetles are out and about!


These insects create a shothole by chewing small holes in the leaves of many different plants.  Their first choice are vegetable crops, then flowers, shrubs and trees.  Though there are many species of flea beetles each species has a specific preference for a different type of plant.  Some flea beetles prefer broccoli and cabbage.  Other flea beetles prefer potatoes and tomatoes.  Above picture can be found at http://insects.about.com .

The adults spend the winter in the ground.  They use protected sites as well as hide under leaves.  The adults are attracted to their host plants by chemicals the plants produce.  The adults will feed over several weeks and then lay eggs around the base of plants.  Once the larvae appear the feeding continues.  The larvae will attack small roots and root hairs.  So watch for these little pests as the weather warms in midspring.  

After the larvae complete their stage in about a month, they pupate.  When these adults emerge from the soil, then we have a second generation of flea beetles in one season.   For all the "shotholing" that
these beetles do on plant leaves, they only effect vegetable plant yields when they  destroy about 10 to 20 percent of the leaf surface.  Repeated attacts can kill plants.  Ornamental plants, edible greens, young seedlings and potatoes can benefit from treatment.

There are various ways of managing flea beetles.  Row covers or screening are good to decrease numbers.  Vacuuming the plants frequently can help control numbers.  Insecticides that are useful are spinosad, permethrin and bifenthrin.  Diatomaceous earth is an effective repellent, but not to be used if you have pets.

So watch for these pests.   They jump like a flea when they are disturbed, but look like a beetle.  Go to Colorado State Universtiy Extension Fact Sheet 5.592 Flea Beetles for more information.

Friday, June 1, 2012

Earth Kind Roses



Earth Kind roses are aptly named.  They are kind to the earth.  The picture above features Carefree Beauty. Texas Agri Life Extension Service states this is a designation given for roses demonstrating superior pest tolerance and landscape performance.  This type of roses limit the amount of fertilizer, water and insecticides necessary to produce a beautiful healthy rose.

For a rose to be designated in this category, they are placed in a trial garden.  The roses are not treated with chemical fertilizers or pesticides and only when it is extremely dry do they receive any supplemental water from a drip system.

To date there are 21 varieties that are labeled as Earth-Kind.  They cover all categories of roses.  These include hybrid teas, floribundas, polyanthus and shrubs.

Listed below are five of the most adaptable Earth-Kind roses:

Sea foam            - rambler grows to 10'
Carefree Beauty - shrub that grows to 6' with pink flowers.
Perle d' Or          - polyantha
Belinda's Dream - shrub that is very vigorous with pink flowers.
Marie Daly          - dwarf shrub grows to 3' by 3' wide.

Texas A&M Agri Life Center puts the roses to the test for eight extensive years of field trial data and research.   Now six other universities have joined in the research.  These are Colorado State University, Iowa State, Kansas State, LSU, University of Minnesota, University of Nebraska. 

The best cultural tips for keeping Earth-Kind roses healthy are planting them in a site with eight hours of sun, good air circulation and a foot of open soil all the way around their base.