Record-breaking warm spring worries eastern fruit growers
When it comes to spring, fruit growers are notorious party poopers. They shiver in their boots when they see revelers cavorting in shorts and sandals on an early warm day of spring.
This year, across the northeastern and midwestern United States, shorts and sandals came out before spring. When snow should still be clinging to orchards on Michigan’s Fruit Ridge, temperatures hit record levels in the high 80s on March 20 and 21. The temperatures beat the old records by more than 20 degrees. Most of the continental United States is sharing the warmth, with the jet stream that normally crosses the country’s midsection trapped in northern Canada. Only the Pacific Northwest from mid-California north is experiencing prolonged winter weather.
Elsewhere, in Michigan and New York, apple trees are at green tip, and growers are already spraying for scab. By some estimates, the season is advanced by nearly a month. And frost-free conditions are not assured until May.
On March 15, marmorated stinkbugs came out of hiding in Washington, D.C. Mosquitoes were being swatted already in Wisconsin.
Early peaches began blooming in late February in South Carolina. Many of the peaches in South Carolina did not get their thousand hours of chilling this year, the effects of which may show up in ragged bloom and misshapen fruit.
Across the Midwest and Northeast, Extension specialists are filling their Web sites with “what to do if” advice on frost and freeze protection, critical temperatures, pollination issues with early bloom, advanced development of insects and diseases, and remembrances of years past when too-warm winter days resulted in lost crops in spring.
In southwest Michigan, Extension fruit educator Mark Longstroth was dusting off some old advice about how to analyze air movement patterns around orchards and improve them using fans or removing obstructions to natural air drainage patterns.
The Great Lakes stayed relatively warm last winter, so there’s no reservoir of ice or cold water to temper conditions and slow fruit tree development. At Cornell University in New York State, Extension educator Mike Fargione noted in mid-January that the mild winter might reduce cold hardiness.
In southeast Michigan, Extension educator Bob Tritten, writing on the Michigan State University Extension fruit news Web site March 21, said: “It has been amazing to see the change in fruit flower bud development from early morning to late evening. This is a spring season that I have not experienced in my 33 years with MSU. In fact, the same is true for most of us involved in fruit farming. The (older) fruit growers among us keep referring to 1945 as the earliest spring bud break that they can remember. We are ahead of that year already.”
On the same Web site, Michigan State University’s Fruit Ridge area Extension educators Amy Irish-Brown and Phil Schwallier wrote, “Degree-day accumulations continue to increase extremely quickly, and we are so far ahead of normal that it’s hard to put a number of days with it. It’s at least a month ahead for degree-days and a little more than three weeks ahead for tree growth stages, compared to 35-year averages.
“As a reference, normal first green for McIntosh (or other midseason varieties) in the Grand Rapids, Michigan, area is around April 11. This year, first green on Macs was March 17.
“I expect that we will get our first scab infection sometime late this week as a rainier pattern seems to be moving our way. Spore monitoring equipment is out and working. Spore development could be delayed somewhat this spring due to little snow cover over the winter. However, the warm winter might offset that. Be ready for scab and don’t miss the first cover sprays—they are important, even with very little foliage present.”
A week earlier, they had written: “I’m almost at a loss as to what to say about the weather this year, but it is what it is. In looking at degree-day totals for the year so far, we are, of course, very much ahead. With the forecasted temperatures, especially the warm night temps, we will move even farther ahead of normal through the next week.”
In southwest Michigan on March 16, Extension educators Mark Longstroth, Bill Shane, and Diane Brown noted that “Apples are moving rapidly past silver and green tip. Exposed green tissue will be susceptible to apple scab. Growth is so rapid that growers will need to shorten their spray intervals to cover new emerging leaves. Materials that are recommended for seven to ten days might need to be applied at three- to five-day intervals. Growth dilution of systemic fungicides will also require shorter spray intervals. It would be well worth watching the weather and trying to apply protectants as close to wetting periods as possible to get maximum protection from your sprays.”
Extension educators at Pennsylvania State said, on March 21: “Primary infection periods for apple scab started two weeks early this year.”
In Missouri, peach trees came into bloom March 18, at least three weeks early. People there recalled that on April 8 and 9, 1973, a blizzard hit northern Missouri with snow up to 12 inches, winds over 40 miles per hour, and drifts 10 feet deep, killing livestock.
That, of course, is the worry. Winter’s not over until it’s over, and nobody knows whether that’s already past or still in the future.