Describe pros and cons of tree injection or infusion.

• A. Most of the pesticide is placed within the tree with little waste; low off-target movement; no heavy equipment; tree injection is good around pavement; cons include nonuniform internal distribution; dose depends on tree size; sap bleeds; long-term effects unknown.
• B. Uniform distribution guaranteed; no drawbacks.
• C. Requires large heavy equipment; always wasteful; not used near pavement.
• D. Has only drawbacks with no benefits.

Answer: (A)

Tree injection or infusion delivers the pesticide directly into the tree’s vascular system, so most of the chemical stays inside the tree rather than in soil or surrounding areas. This targeted approach reduces off-target movement and can be convenient in places where soil applications or drift would be a problem, such as near pavement, since there’s less risk of surface runoff or exposure to pedestrians and non-target plants. It also often means you don’t need large amounts of soil-applied equipment, which can be beneficial in tight or urban settings.

But this method isn’t perfect. The chemical tends to move with the tree’s internal flow, which can be uneven, so the distribution within the tree isn’t guaranteed to be uniform. Because dose is typically scaled to tree size and species, getting the right amount requires careful planning; mis-sizing a tree can lead to ineffective control or phytotoxicity. The wounds created by injection can cause sap bleeds, which may be unsightly or attract other issues at the entry points. And because we’re still learning about long-term effects, there’s some uncertainty about how repeated injections affect tree health over time and how the chemical behaves in the tree long term.

Other statements imply uniform distribution is guaranteed, or that injection always requires heavy equipment, or that there are no benefits. In reality, uniform distribution is not guaranteed, injection methods can be done with relatively small tools, and there are clear benefits in reduced environmental exposure and site disruption when used appropriately.