Fast-growing, upright shoots appearing suddenly on trees and shrubs often confuse those maintaining their plants. This vigorous growth emerging from unexpected places leads many to wonder if it will mature into a strong, permanent branch. Understanding the nature and origin of these shoots determines whether they are a welcome sign of health or a detrimental response to stress.
Identification: Water Sprouts and Suckers
These vigorous shoots are categorized into two types based on their origin: water sprouts and suckers. Water sprouts develop on the trunk or from the larger, older branches of the tree’s above-ground structure. They typically grow near-vertically, appearing soft, green, and lacking the rough bark of established wood.
Suckers, by contrast, emerge from the root system or the base of the tree, often below the graft union on grafted plants. Like water sprouts, they exhibit rapid, upright growth and compete with the main tree for water and nutrients. Differentiating them is important because suckers on grafted trees carry the genetic characteristics of the rootstock, which is usually an undesirable variety.
Structural Future and Growth Triggers
Water sprouts and suckers rarely develop into structurally sound or permanent branches that contribute positively to the tree’s framework. They originate from dormant buds held beneath the bark, often lacking a proper branch collar for strong attachment. This weak connection point makes them highly susceptible to breaking under the stress of wind, ice, or a heavy fruit load.
The rapid, vertical growth of these shoots is often a tree’s physiological response to significant stress or injury. Common triggers include heavy or improper pruning, such as topping, which dramatically alters the tree’s hormone balance. Environmental stress like drought, soil compaction, disease, or physical damage can also stimulate the growth of these epicormic shoots. The tree is attempting to recover lost leaf area or reacting to an imbalance in its internal energy reserves.
Correct Management and Removal
Because water sprouts and suckers divert energy from desired growth and create structural weaknesses, their removal is recommended. The most effective time for removal is when the shoots are young and soft, allowing them to be rubbed off easily with a gloved hand. This technique, known as “rubbing off,” removes the shoot cleanly at its base and destroys the dormant bud, reducing the likelihood of immediate regrowth.
For larger, hardened sprouts, they should be pruned as close as possible to the point of origin, ensuring no stub remains. Leaving a stub can prompt the growth of multiple new sprouts from the wound, exacerbating the problem. Removing suckers is particularly important on grafted plants, as leaving them allows the rootstock to out-compete the desired upper portion of the tree.
Preventing the formation of these shoots centers on minimizing the factors that cause the tree stress. Avoiding severe, indiscriminate pruning and maintaining proper tree health through adequate watering and mulching reduces the tree’s need to produce these reactionary growths. Addressing underlying issues, such as poor soil or pest infestations, is more effective for long-term control than simply cutting off the sprouts after they appear.