Some of the guys over at the B&B Pitstop Cafe were arguing the other day about 'suckers' in corn. The older fellows remember being sent to the fields as kids to pull 'suckers' off the corn plants because their fathers said 'suckers' were bad for the corn, although some suspected that the real purpose may have been to simply keep them out of their father's hair on hot, muggy summer days. Well, what are 'suckers' and are they bad for corn?
'Suckers' in corn are more properly termed 'tillers' and are auxiliary corn plants that develop from one or more stalk nodes (joints) at the base of the main stalk, one tiller per node. Tillers become nearly independent plants as they develop, partly due to the fact that they will eventually develop their own root system. Tillers may compete somewhat with the main stalks, but given their late developmental start they usually lose out in the competition for water, nutrients, and light.
One or more tillers commonly form if the main stalk is injured or killed by hail, frost, insects, wind, tractor tires, little kids' feet, deer hooves, etc. If the damage occurs early enough in the growing season, such tiller development may result in harvestable ears. Late tillering, however, usually doesn't allow enough time for tiller ears to develop and mature before a killing fall frost. An example of late tillering occurred in some Indiana fields damaged by the late June frost of 1992. The apparent 'regrowth' of these fields looked promising from windshield surveys, but little if any grain yield was obtained from these damaged fields.
Tillers may develop in undamaged fields, also. Most agronomists agree that such tiller development is a signal that growing conditions are very favorable, with few limitations on available nutrients, water, or light. Favorable growing conditions may exist simply due to favorable weather conditions or because the plant population is too low for the productivity level of the field. With favorable growing conditions, the corn plant has ample energy and nutrients to 'invest' in tiller development. Some hybrids are also genetically prone to developing tillers, even at adapted plant populations.
As a rule, the end result of tiller development in an undamaged field is neutral. Usually, the main stalk will outcompete the tillers and the tillers eventually wither away. Tiller development in a field that was damaged or simply planted too thin MAY result in harvestable ears and thus contribute to grain yield.