Question
Biology Question on Secondary Growth
Age of a tree is determined by
height of the tree
annual rings
no. of branches
both (a) and (b)
annual rings
Solution
Annual ring is the wood formed in a single year. It consists of two types of wood spring wood & autumn wood. The transition from spring to autumn wood in an annual ring is gradual but the transition from autumn wood to the spring wood of the next year is sudden. Therefore, each year?? growth is quite distinct. The number of annual rings corresponds to the age of that part of the stem. They can be counted by increment borer. Besides giving the age of the plant, the annual rings also give some clue about the climatic conditions of the past through which the plant has passed. Dendrochronology is the science of counting and analysing annual growth rings of trees.