A reduced cluster count and an average berry set portends an average-sized Concord grape crop at best, according to James M. Kamas, the Cooperative Extension Service's regional grape specialist.
The five-year average production of Concord grapes is 112,000 tons, with last year's 105,000 tons the low figure and the 127,000 tons of 1987 the high amount, according to the state Agricultural Statistics Service. Most New York Concord grapes are grown in Chautauqua, Erie and Niagara counties.
The demand for Concords, especially popular in unfermented juice, has strengthened since 1986. Last year's Concords brought prices that on occasion reached $250 a ton on the open market. And the National Grape Cooperative (Welch Foods), the largest single producing agency, reported 1989 member earnings of $275 a ton, according to the 1990 New York Economic Handbook.
While growers naturally might have preferred to hear predictions of a larger 1990 crop, they were cheered by Kamas' view that the adequate moisture of May and June is reflected in a "desperately needed" revitalization of the vines. Kamas said that the 1990 low cluster count is a consequence of the crop stress of 1987 and the moisture stress of 1989 and 1990.
"Unlike the past two growing seasons, adequate soil moisture levels have been very favorable to shoot growth and development," Kamas noted. "Vineyards that have lost vine size over the last two years appear to have an excellent opportunity to recover this season."
To increase berry size, Kamas recommended that growers act to limit the growth of weeds that compete with the vines for moisture and nutrients.
Currently, grape specialists report that grapevine disease pressures -- black rot and downy mildew -- are low in most vineyards.