Yet synchrony allows a farmer to spray herbicides, cultivate, irrigate, and most importantly harvest in a single operation. Synchrony is a remarkable feat of coordination by the plants. Days or weeks may elapse between leaf, tiller, spikelet or floret initiation, and yet each plant flowers at about the same time and grain ripens simultaneously within the span of a few days. The observed synchrony of crop development cannot be achieved without the coordinated responses of a number of developmental processes to the environment. How this coordination between plant and environment is achieved is largely unknown.
Farmers often use benchmarks to track corn development and time various management operations.
The accuracy of some of these statements may be debated, but the reality is often borne out of careful observations by farmers in their environment. In southern Wisconsin, each corn plant typically develops about 20-21 total leaves, silks about 65 days after emergence, and matures about 120 days after emergence. All normal corn plants follow this same general pattern of development, but the specific time interval between stages and total leaf numbers developed may vary between different hybrids, seasons, planting dates and locations. An early maturing hybrid may develop fewer leaves or progress through different stages at a faster rate than indicated here. A late maturing hybrid may develop more leaves or progress more slowly than indicated here.