As temperatures start to warm each spring, questions arise regarding apple crop development. A resource easily overlooked in agriculture is the extent to which growers – and other industry folks – use scientific data. Crop development is a perfect example where we can quickly alleviate any concerns about the crop by using the mountain of data available from automated weather stations.
Riveridge growers take advantage of Michigan State University’s Enviroweather network of internet-connected weather stations throughout Michigan. With a mix of historical and current season data, we can track our crop development this season and compare it to previous seasons.
Empirical data for the Sparta, Michigan, or “Ridge” area, have shown that Green Tip (the first visible sign of foliage) occurs around 127 Base 42F Degree Days in McIntosh. Growers have used this as their baseline to judge development of the entire crop for years. As you can see by the graph, we are on track for a slightly earlier Green Tip, but not anything that is concerning. In fact, this may result in an apple harvest that is slightly earlier than last year.
The winter was milder than the last few and that will result in less winter injury to the trees. A warm beginning to March gave us a jump start toward tree development, but the final weeks of the month have returned to near normal temperatures and has delayed progress.