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November 2012


If I had to pick one pest that has the most potential for harm to our fruit industry, it would be Leucostoma Canker, aka Cystospora,  aka Gumosis.  Currently we have no “silver bullets” to deal with this issue.  I would like to get a better understanding of this disease, its impacts on the industry and our knowledge of it. 


Problems are best solved in logical steps. Here is an example of one approach.



* Can you state the problem in your own words?

* What are you trying to find or do?

* What are the unknowns?

* What information do you obtain from the problem?

* What information, if any, is missing or not needed?





With step #1 in mind, please reply back to the following questions:

  • Is gummosis a problem in your orchard (1 none – 10 severe)?

  • Does it impact your productivity (1 none – 10 severe)?

  • Does it impact certain varieties more than others?  Which?

  • What do you know about this disease?  Please list your thoughts on what you think you know about this disease.


Please email me back with your thoughts on the above questions.  If there’s enough response maybe we can build some consensus on the problem.  Every year I see several pathologists from the Northwest at winter meetings.  I hope to get them involved with our “problem”.



Over the next month the Cropworx crew will be working on putting a website together.  We would greatly appreciate some feedback on what you would like to see on our site.  What information, what content is of value and practical use for your business.


 As long as I’m in feedback mode, are there items or type of materials that you have a difficult time sourcing for your operation?  If yes, please let me know what it is.  It’s possible that others are fighting the same battle and the power of a “group” may resolve the issue.




The following came to me from Curt Swift:

Jude Sirota, former Mesa County Weed and Pest Manager, and I, Curtis Swift former CSU Extension Horticulture Agent, have scheduled a workshop for private and commercial pesticide applicators to be held at the Country Inn at 718 Horizon Drive in Grand Junction on December 14.

The workshop has been approved by the Colorado Department of Agriculture for Continuing Education Credit for all the general categories as well as turf, ornamentals, ag insects, ag weeds, and rangeland weeds/industrial right-of-way. The details of the program and a registration form can be found at at
We will also be hosting a similar workshop in the spring for those of you unable to obtain the credits you need to maintain your applicator certification this winter. Each of the 1/2 hour morning sessions will provide the required 1 CECs
except for Laws and Requlations. The two one-half hour sessions on Laws and Regs will provide the two credit hours required.  By attending the morning sessions a private applicator will obtain all the credit necessary to maintain their private applicator license. The afternoon sessions in breakout #1 will provide the 2 credits required for those holding the ornamental and turf categories.  Breakout #2 will provide the credits to maintain their license in AG Insect or AG weeds (one credit). Applicators can also receive a credit for either Industrial Right of Way Weed Control or Rangeland Weed Control.

Curtis Swift, Ph.D.
Swift Horticultural Enterprises, LLC
Swift Horticultural Consulting
High Altitude Lavender



You cannot help the poor by destroying the rich.

You cannot strengthen the weak by weakening the strong.

You cannot lift the wage earner up by pulling the wage payer down.

You cannot further the brotherhood of man by inciting class hatred.

You cannot build character and courage by taking away people’s initiative and independence.

You cannot help people permanently by doing for them, what they could and should do for themselves.

- Abraham Lincoln




These “rules” were originally developed for pruning apples, BUT… if you’re growing fruit on a tree these rules will apply. As you read these rules think about the concepts that they were developed from:  The most productive blocks are ones that have a minimum of structure wood and a maximum of young fruiting wood.  They are also the ones that capture (use) the maximum amount of sunlight from the top to the bottom of the tree.  To achieve both of these goals you have to continually remove excess structure wood and cycle in new fruiting wood.




  • Start pruning the tree from the top downward, outside inward.  This removes the chances of a top heavy tree.  It forces you to balance the tree and eliminates the chance of leaving too many branches (structure wood) in the top because you pruned too much off the bottom of the tree.

  • Remove laterals (big branches) with diameters that exceed 50% of the branch they originate from.  Look for the “big” branch and cut it out.  Look at the tree from a distance before you start to determine which “big” branches need to be removed. This rule applies both to branches originating from the central leader and side branches off of scaffold limbs.  This process removes dominating laterals, distributing vigor throughout the tree.  A tree with “distributed vigor” will naturally grow more fruiting wood.  On pome fruits use “stub” cuts which will produce soft re-growth and fruit buds.

  • Stub off vigorous uprights to redirect energy and light through the tree.  With stone fruits it’s critical to remove these from inside the interior of the tree.  On pome fruits a stub cut “upright” will often produce weaker horizontal fruiting structures.

  • Remove weak, pendant fruiting structures.  This rule will help keep the “fruiting wood” in your tree young.  Removing weak branches increases light penetration and thins off weaker spurs which saves on chemical or hand thinning later.  Weak spurs or fruiting buds often bloom at a different timing, and persist with poor quality crop until removed.  Dormant pruning will invigorate the area and direct energy into production of higher quality buds that are better able to withstand spring frost.

  • Do not allow too many branches in the tree, even if they are below the 50% rule.  Excess branches “tax” the system and reduce light penetration.  Experience will tell you where the balance is that allows for production of maximum fruit numbers and size.

  • Prune towards a goal.  Have an idea of how many boxes of fruit you want to harvest off of each acre.  Work that number backwards to determine how many fruit per tree you need, then prune towards that number.  Prune a few trees and count the fruiting sites left.  Following this rule will reduce your thinning bill and increase your fruit size. Put a note on your calendar to count fruit per tree just prior to harvest.  This timing allows you to judge crop load and fruit size.   TAKE NOTES!  When pruning and thinning time comes around the following year you will be able to take most of the guessing out of  your work.



All of us who farm have one of our most critical “inputs” delivered to us daily at no cost!   SUNLIGHT.  Sunlight is what drives the system.  It’s what gives your fruit taste, size and color!  Following these rules will help you take full advantage of one of your greatest resources, the sun.


If you have questions about these rules, let me know and I’ll explain them further.  I’d be happy to demonstrate them on your place.  It’s a good time of year to plan for the coming season, if you would like to discuss herbicides, fertilization, or pest programs give me a call and I’ll stop by.


“I've learned that people will forget what you said, people will forget what you did, but people will never forget how you made them feel.” 
― Maya Angelou


Best Regards,


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