Two types of lodging have been identified, stem lodging and root lodging. Stem lodging results from the bending or breaking of the lower culm internodes, whilst root lodging is due to failure of root anchorage and results in straight, unbroken culms leaning from the crown. Debate is continuing amongst scientists and growers as to whether stem lodging or root lodging predominates. Whatever the form of lodging, it is generally agreed that it is due to an interaction of the plant with the characteristics of the rain, wind and soil. Rain increases lodging risk by decreasing soil strength and increasing the load which the plant must bear.
Wind then acts as the force which pushes the plant over or buckles the stem.
It is envisaged that their influence on lodging risk is through their ability to alter crop structure by affecting certain plant characteristics. The complex interaction between husbandry, weather and soil which can result in lodging is poorly understood. Consequently guidelines for reducing lodging are often based on perceived wisdom rather than comprehension, and this has resulted in widespread lodging occurring too frequently. It also needs to be emphasised that lodging events themselves have been rarely observed in any scientific way, although the results of these events are of course only too obvious. This is due simply to the unpredictable nature of such events in both spatial and temporal terms, and the difficulty of making field measurements in often hostile weather conditions.