Terms to understand

Every discipline and industry have their own set of terms. Many of these terms are everyday words but become specialized within a discipline.

Arboriculture is no different. Sometimes it is helpful, even necessary, to know and understand the term in order to fully grasp the context of the discussion. Other times, well, maybe we have some wiggle room. Let’s take a look at a few.

Feeder roots vs absorbing roots These roots are small roots that branch off larger roots. The argument here is technically the correct term is “absorbing roots”. This is because roots are actually absorbing water from the soil in order to access not just the moisture but nutrients from the soil which enter the plant through this dynamic pathway. (This presumption goes with the premise that most roots are, in fact, in the soil.) These nutrients are essential to the growth and survival of a plant, but do not supply food. (Think vitamins and minerals in our diets. Important, but you need the bulk of the food as well, not just the vitamins and minerals contained therein.)

Many people call these small roots “feeder roots” leaving the impression the tree is taking up food to feed itself. Which, technically, is incorrect. The “food” for the tree are the carbohydrates produced in the leaves through the process of photosynthesis. https://mcneillstreeservice.com/2018/11/30/understanding-photosynthesis/

Now that is clear as mud, right? And is why you will hear so many people refer to “feeder roots” as opposed to “absorbing roots”…both lay people and professionals. This confusion is exacerbated by fertilizer propaganda which promotes “feeding” your plant or tree with their product.

It is a good idea to become familiar with both terms to understand what someone is trying to say, whether or not they are technically correct in how they are saying it. I generally let this one slide as opposed to correcting people, unless the conversation is specific to understanding the physiology of the plant.

Seal vs heal I have already written a blog on this one, https://mcneillstreeservice.com/2017/12/07/trees-dont-heal-they-seal/ so will keep this short. Trees seal. People heal. Now the argument here can go on f-o-r-e-v-e-r. But the premise is trees don’t reproduce tissue that specifically replaces lost tissue like humans do. They compartmentalize the injury, in essence walling it off from new growth, but the injury is always there. It is just encapsulated. I don’t get too fussed about using these terms interchangeably. Clients are more apt to use “heal” and I seldom correct them other than to explain the physiological difference between the two reactions to injury. Some professionals feel it is an indication of ignorance on the part of other industry professionals if heal is used as opposed to seal.

Vigor vs vitality From ISA Glossary of Arboricultural Terms 2006: “Vigor – overall health. Capacity to grow and resist stress. Sometimes limited in reference to genetic capacity. Vitality – overall health. Ability of a plant to deal effectively with stress.”

From A New Tree Biology, Shigo “Vigor is the genetic capacity of an organism to resist strain. Vitality is the ability of an organism to grow under the conditions in which it finds itself.”

Okey, dokey. I looked up several other sources for definitions of these two words; overlap and vague terminology predominated. Seriously, in my humble opinion, if you slip up and use one as opposed to the other, I think most people will get the gist of what you are trying to say.

If you are writing a technical paper or trying to impress the genetic capability of a plant as opposed to its innate ability to thrive in a non-native situation, then using the correct term will be more important.

Dirt vs Soil Dirt is soil without a job. You could say the same about rope vs line.

Whereas this is another situation I don’t get too fussed over when talking with a client, I will take the opportunity to introduce the subtleties within the concept of soil health, thereby emphasizing the better quality as a growing medium.

The photo below illustrates poor dirt as opposed to quality soil. This is compacted with little to no active biology.

The next photo shows a well-aggregated soil with plenty of live biology ready to go to work.

Variety vs cultivar Variety: a naturally occurring subdivision of a species. they will have distinct differences and can breed true to that difference. Cultivar: a shortened term for cultivated variety of a plant. This is a manmade variety; it cannot be reproduced naturally. The usual propagation method is asexual (cloned).

The following link to Iowa State Extension gives the clearest explanation of these terms I have found to date. https://hortnews.extension.iastate.edu/2008/2-6/CultivarOrVariety.html

Topping vs Reduction These are two terms to definitely understand as they pertain to pruning. Topping is a term that was commonly used in the past often involving the removal of a large portion of the canopy of a tree. The problem being there was no rhyme nor reason to the method or technique resulting in a great deal of long-term damage. This practice is now considered unacceptable, denoting work performed by a sub-standard tree care company.

Reduction is the systematic removal of limbs back to a point where the tree has a reasonable degree of ability to maintain the stem that is left. Reduction is often warranted when the height of the tree or horizontal stretch of a limb presents a situation where failure could cause injury or property damage.

The photo below, taken in 2019, shows a row of hybrid poplars topped several years ago. Many are declining and dying.

In January of 2013, this row of pines (shown below) was reduced in height due to close proximity to the house. The clients did not want to remove the trees but desired increased stability. To date, there is no sign of decline or dieback on any of the trees in this row.