In woody plants, the epicormic shoot is a bud, which sorbs from a latent bud, or from a bud that has remained dormant for an indefinite number of seasons.
For this reason the suckers are formed from the stems or woody branches of several years of age, generally at their base.
The most evident characteristic of the epicormic shoot is that of being very vigorous, of rapid growth and with a marked vertical development. The epicormic shoot, due to its trophic competition against other shoots, tends for this reason to take over, subtracting nutritional elements and sap from the entire balance of the plant. For this reason, in ordinary production pruning, the epicormic shoot is subject to cutting, except for the need for a restructuring of the geometry of the plant.
Another of the characteristics of the epicormic shoot can be that of the presence of thorns, as happens for example in citrus fruits.
The sucker, due to its vegetative characteristic, is also called ricaccio or cacchio and for the vegetative aspects it is similar, even if in a different position, to the epicormic shoot.
From the systematic point of view, various types of suckers are distinguished:
– natural epicormic shoot, the one that comes immediately from the graft and from any branches or branches;
– wild moss, the one that appears below the graft and the trunk itself;
– semi-epicormic shoot, which is less strong than the previous one, but which comes from the same part of the tree;
– artificial epicormic shoot, what is intentionally developed, in order to correct any defects in the skeletal scaffolding of a plant or replace deteriorated branches.
Another classification that is often made in the agricultural way of epicormic shoot is that which, in jargon, defines them between male and female suckers; the first are the actual epicormic shoot (they do not have other secondary branches), the second ones have secondary branches (sometimes they can evolve, in some species of fruit tree, fruit trees).
From the physiological point of view the emission of the epicormic shoot, is a process of compensation that the plant puts in place to rebalance the vegetative condition between root system and aerial apparatus. In fact, in case of deficiency in the branching, there is the germination of a certain number of adventitious buds with consequent emission of epicormic shoots.
A typical exuberant emission of suckers occurs when the hair undergoes a drastic and sudden curtailment due to mechanical traumas, fires, more or less drastic cuts. The emission of the epicormic shoots is also an ordinary event in the species with bushy habit or basitonous when they are pruned according to farming methods whose geometry differs more or less considerably from the natural habit.
Also the form of breeding of the plants can stimulate or not the emission of epicormic shoots. This is the case of the basitonous-bushy growth of the olive which, if pruned in a polyconic vase, tends to emit a considerable number of suckers, every year, from the center of the crown, while, this emission, is less intense in the forms raised to monocone or to globe.