Volunteer Newsletter, March 4, 2006

We had such a good time in January, we're doing it again with the Valley of Heart's Delight.  We'll be feeding the hungry in several cities, and keeping a few thousand pounds of fruit from going to waste.  If you plan to join in, please RSVP to joni@villageharvest.org.  This time the forecast is calling for a bright sunny day! 

Saturday, March 11th
8:30am - 12:30pm
Valley of Heart's Delight, Foundation for Global Community
222 High St, Palo Alto

Instructions for harvesting volunteers:

• Dress in layers for a cold morning and warming during the day, with sun protection, and insect repellant in mind.
• Wear comfortable, covered shoes.
• Come prepared to carpool.  Please let us know if you have a truck or SUV to help carry fruit.
• Bring a small box or bag to share in the harvest. Tree ripened fruit from Santa Clara Valley... it doesn't get any better than this!
• Children 12 and over are welcome but please see our Volunteer FAQ's for more information.

While many of you may have been enjoying the relatively warm winter that we've had this year, the local orchardists and Village Harvest coordinators have been fretting.  Did we get enough chill hours?  Did they come early enough? 

But what is a chill hour?  Why do we care?

Here's a layman's explanation from the University of California.  "In the winter months, the tree's internal processes are in a state of rest, known as dormancy, due to the presence of growth inhibitors. Growth will not occur even under ideal temperature conditions. This prevents the trees from beginning to grow during atypical periods of warm weather only to become damaged by normal freezing temperatures later on in the winter or early spring." 

"Dormancy is broken when sufficient cold temperature breaks down the growth inhibitors within the tree. This is called vernalization, "chilling," or "winter chill." A specific number of cumulative hours of chilling (temperatures between 32°F - 45°F), are required to break dormancy, which varies from variety to variety. Once the appropriate number of hours of chilling have been achieved by a variety, active growth resumes in the spring, but only after trees are exposed to warm enough temperatures for natural growth processes to begin. Most of Northern California receives between 800 and 1,500 hours of vernalization each winter. Southern California may only receive 100-400 hours."  Or that used to be the case. 

Silicon Valley used to be home of the most wonderful Bing cherries.  These trees like to have 700 chill hours.  For the last several years, Silicon Valley has gotten about 400-500 chill hours.  Additionally, according to the old time farmers, the heat from pavement and furnaces can cancel out chill hours received.  So the Bing's haven't been getting enough chill hours and anyone with a Bing cherry tree in Silicon Valley may have noticed that they haven't gotten many cherries. 

In 2006, Morgan Hill is reporting 600 chill hours (San Jose no longer has a weather station since BAREC is no longer operational).  San Jose's chill hours have tended to be 2/3'rd that of Morgan Hill.  At 400 chill hours, it's low for Bing cherries and right at the minimum of what many of the apricots, prunes and apples want in order to break their dormancy, flower and set fruit. 

So will we have summer fruit to harvest?  We'll just have to wait and see.  Meanwhile, enjoy the early blossom time =)

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