Understanding the "root system".... (growing, trees, Arizona, leaves)

[CArizona]

What causes part of a tree or plant to be undernourished? Most of the tree can be bushy and healthy yet one side or a corner of the tree might be dry and brittle with few leaves...I'm trying to gain a better understanding of how the "root system" works when it comes to distributing water and nutrients to all parts of a tree or plant etc...My husband had the "green thumb" in our family but he passed away a few years ago and I'm on my own when it comes to gardening today. Thanks ahead of time for your "help!"

[J&Em]

This is a topic of whole chapters in botany textbooks. I tried really hard to find some simple diagrams/pictures to help do it in a few words.

Basically the roots of a tree are spread out all around the tree just like the branches are above ground. Each root has many divisions (just like the branches on moe so and much tinier at the ends) and it is near the very ends that water and nutrients are "sucked" up for lack of a better word and passed along up through the trunk in a series of "tubes" (like straws) that then carry the moisture and nutrients out to each branch and leaf.

If a root grows around other roots it can choke the other roots and damage itself causing less and less flow up the "tubes" to that part of the tree. This might cause part of the tree to begin to die.

Diseases and pests can often attack the roots and prevent the water and nutrient flow as well with the same partial death or damage to the tree.

Sometimes there is physical damage to the roots from critters like voles or moles that damage the roots or damage the bark at the point where the tree emerges from the ground which stops the water and nutrients from passing up the tree.

Rarely a lightening strike to the tree will damage both the central core of "straws" on one side of a tree and the roots where the lightening discharges into the ground and leave half the tree damaged but the other half growing.

Some help in visualizing the tree roots and tree here: transpiration and here: Lesson 6 | Tree Kit | Illinois Natural History Suvey

[CArizona]

J&Em...Thank you! Your post and explanations definitely helped! I am trying to gain a "knowledge base" and some confidence when it comes to gardening...It's so easy to become discouraged at first and assume that some people have a "green thumb" and others don't and never will!...My husband seemed like such an expert and so confident. I should have paid closer attention and asked him more questions. But it's never to late to learn new things! Right? Thanks again!

[no kudzu]

May I add to J&Em? Remember the feeder roots are in the top 6 inches of the soil. Anything deeper is usually for holding the plant in the soil. The tap root does not "tap" into any water-it just holds the plant in.

Sometime we kill our plants or parts of our plants with too much water and if you don't have good drainage you are just soaking your plant in a soil bowel of water and if you have clay soil it can really be bad.

The old theory was to amend soil with lots of compost, sand etc for better drainage- at least for trees- but now botanist are saying that creates a false area of easy growth and then when the roots hit the unamended soil it is like hitting a brick wall. But old habits die hard and I still amend especially with shrubs and my whole bedding areas are very much amended.

I like to do post mortem on my dead plants and my usual problem is moles or voles who get to roots on one side more than the other. A die hard gardener will plant in an area dug up and encircled with some kind of screen or chicken wire or something with smaller openings to keep undergroud critters away. too much trouble for me. This is essential with bulbs.

But mostly J&Em did a good primer on roots.

[J&Em]

Originally Posted by no kudzu

May I add to J&Em? .....

LOL of course you may. Real knowledge is always welcomed and appreciated.


CArizona you are welcome and I hope it gave you a start to understanding green things in general. Trees, shrubs and many plants have more in common than people realize. Once you begin understanding a bit about one group you also understand a lot about the others. I also just realized that you asked a question about roots but they aren't always part of the problem you described. Sometimes a branch can be physically damaged and gradually die off. This can be caused by storm damage, frost damage or any number of bugs, bacteria and fungi.