February 2010

 

State lawmakers working to fill a $1.5 billion budget shortfall over two years have proposed charging a 2.9 percent state sales tax on things including candy, soda, downloaded software and pesticides.   Nine bills that suspend or eliminate tax exemptions will land on Gov. Bill Ritter’s desk this week.  Removal of the exemptions  are part of an overall plan pushed by Ritter to balance not only next year’s budget, but also the current one.  (excerpts from the GJ Sentinal)

House Bill 10-1195 has passed both houses and is headed to the Governors’ desk to be signed into law.  This new law is scheduled to take effect March 1st.  This means that after that date all pesticide purchases will be taxed at 2.9%.  Give me a call if you have questions or would like to discuss options.

 

The last several seasons powdery mildew on cherries has become more and more of an issue.  The following information on cherry powdery mildew control is from Lynn Long with Oregon State University.

Early season identification and spread

By shuck fall it may be possible to see the first mildew colonies appearing on leaves. This is called the primary infection since the colony was established from overwintering spores. These will be small white spots with a powdery appearance. In the early season, look for infected leaves in the tree crotch or on root suckers, where leaves are succulent and humidity is high The white powdery spores are called conidia. Conidia spread the disease during the late spring and summer causing additional secondary infection. As the disease progresses, colonies will spread to cover more of the entire leaf surface. Infected leaves may be somewhat distorted and colonies may be found most easily on the underside of the leaves. Tree centers and root suckers are still the best place to find the disease. 

Fruit and late season infection

The initial stages of fruit infection are difficult to identify. It is often necessary to look across the cherry so as to view the white powdery spores as they stick up above the horizon. You will need a hand lens at this stage to properly identify. Be careful! Sometimes dust can be misidentified as spores. As the infection progresses the white powdery spores become more obvious and pronounced and identification can be made without a lens. Eventually, the infected area becomes sunken and pitted.

By mid-summer, overwintering spores are beginning to form on leaves. The overwintering spore is called an ascospore and it develops within a cleistothecium. The cleistothecium appears on leaves as a small ball, visible to the naked eye. It is the ascospore that starts the infection process the following spring.

Conditions for primary infection

Typically, it takes 1/10 inch of rain (or irrigation) and temperatures of at least 50º F in the early spring for primary infection to occur.  The summer stage differs in that there is no need for rain, only high humidity. However, in the Mid-Columbia, conditions of high humidity most often occur after a series of light showers that raise the humidity during warm weather. Ideal conditions for the spread of the disease during the late spring and summer are simply high humidity and temperatures of 70º F to 80º F. Control

The key to control of the disease on the fruit is to keep the disease off the leaves.  This means a regular, consistent spray program from shuck fall to harvest

There are a number of fungicides available with several different modes of action.  Be sure and change your program from year to year and rotate modes of action within the season.

 

 “Try not to become a man of success. Rather, become a man of value.  A successful man takes out of life more than he puts in.  A man of value will give more than he receives.”   Albert Einstein

 

If you’re growing cherries you need to spend some time on Lynn Long’s website.  It has lots of valuable info on pests, training, varieties, irrigation and on and on…..

http://extension.oregonstate.edu/wasco/horticulture/Horticulture-.php

 

Tim Smith with WSU  is the best source I know for information on fireblight.  That season will be here before you or I are ready!  If you had fireblight outbreaks in your orchard last year it’s worth your time to take a look at Tim’s website and brush up on your knowledge.  Cougarblight, a fireblight prediction model is also available at this sight.

http://www.ncw.wsu.edu/treefruit/fireblight/principles.htm

 

 

Horticultural Mineral Oil on Cherry

 

In tests conducted by Dr. Gary Grove, spray oils (Stylet and Omni oils) were found to effectively and safely control powdery mildew when used prior to pit hardening. Stylet oil provided control equal to or better than most DMI type fungicides such as Rally and Rubigan.  Besides effective control, oils have at least two other advantages. 1)Oils act as both an eradicant and a protectant, providing the destruction of lightly established infections while protecting the leaves from the establishment of new mildew colonies. 2) They provide an alternative mode of action, thereby reducing the likelihood of resistance to current fungicides. In Groves early work, phytotoxicity became an issue when Stylet oil was applied on a season-long basis. Current recommendations, however, call for only two oil applications. Both must be applied prior to pit-hardening (damage can occur with later applications). The first application should be made at shuck fall. A 1% solution will protect leaves for 10 - 12 days, while a 2% solution is effective for 14 - 18 days. It should be kept in mind that leaves emerging after the application, are susceptible to infection.

 

• Apply prior to pit hardening.               

• Don’t apply within 14 days of a micronized sulfur application, follow the label.

• Don’t apply azinphos-methyl before, during or after an oil application.

• Don’t apply oils with spreader stickers, Nu-Film-P or Nu-Film-17 (pinolene based products)

• Don’t apply when temperatures are in excess of 90ºF. There have been no reports of damage when applications were made when temperatures were below 90ºF but climbed above 90ºF later in the day.

• Don’t apply 24 hours before or after a frost.               

• Don’t spray oil on heat or water stressed plants.

• Don’t spray oil on wet foliage, as oil will simply run off.                       

• Don’t apply to Lapins?

 

The US EPA has approved expansions in the label for Altacor, a reduced-risk insecticide produced and marketed by Du Pont. Among the changes are removal of restrictions on the use of oils or adjuvants with Altacor applications to pome fruits and stone fruits, a reduction of the preharvest interval (PHI) in pome fruits from 14 to 5 days, and revision of the PHI to 7-10 days in stone fruits where application rates are 2-3 ounces per acre. Primary targets for Altacor are Lepidopteran larvae such as codling moth, peach twig borer, oriental fruit moth, and leafrollers; effectiveness against other pests remains a topic of field research. The new label is posted on cdms  at http://www.cdms.net/LDat/ld8KE008.pdf.

 

Check the web sites listed below.  They contain new grower guides for organic production of apples and grapes.  Don’t have either crop?  Take a look anyway.  There’s lots of info that will translate to whatever crop you have on your farm!

http://www.nysipm.cornell.edu/organic_guide/apples.pdf

http://www.nysipm.cornell.edu/organic_guide/grapes.pdf

I also have organic pest control programs (from another source) for any of our fruit crops.  If you would like a copy give me a call.

 

 “Politics is supposed to be the second-oldest profession.  I have come to realize that it bears a very close resemblance to the first.”     Ronald Reagan

 

As always!  Please call me with any questions.

Larry  234-3424