Hello! This is my first post on this wonderful site. In the past almost 5 years of new ownership of a Houston 1950's rancher, I have had to remove 5 borer-riddled mature Arizona Ash trees from my suburban corner lot (note to self - if trees are important to next home buy, have them inspected before purchase - lol). The first was removed 4 1/2 years ago and the most recent, last spring. When walking on my lawn, I have noticed "sink holes" or indentations that I attribute to the degradation of the old tree roots. Has anyone else had this experience? If so, about how long should I wait before attempting to re-grade (or at least smooth-out) the affected areas? At first it was just an issue of appearance but now I am concerned that someone will turn an ankle or worse when walking there.
I am a relative "newbie" to gardening but am eager to learn. I would appreciate any advice you have to offer.
Impact of Removed Mature Trees on Lawn Grade
Hi there, GardeningLwr, glad you popped in!
I had almost all of my pine trees removed just over 3 yrs ago. One of those was located where I still have lawn, and I have the sinkhole thing going on, too. You probably already know this, but the problem is due to the rest of the stump and roots decaying, which takes up less space, which causes the sinking. The advice I was given a couple of years ago is to add a mix of topsoil and sand, topped off with compost. The topsoil and sand will fill the area without subsiding too much, the compost will keep good soil stuff going for your turf. You'll probably have to keep adding some sand and compost each yr (maybe even a few times during the growing season) until the subsiding stops, but you should always leave a couple inches of grass blades showing so the grass will grow up to the new soil level.
Hope that helps! I know others will come along and chime in, as well.
Maggie
I have a lot of old pecans and oaks so I lose trees. After they're cut and stump is ground, I add some topsoil to even out the spot. I usually repeat this again the following year, as hole sinks a little. Have never had to do refill a third time.
GardeningLwr,
Having broken my ankle in three places after stepping into a hidden low spot, I suggest filling the low spots now, but do so with soil that matches what is there already. Otherwise, you may find youself watering and fertilizing that spot more often. Also remember that clay, sand and an organic material form adobe. Using sand is not recommended now-a-days. Years ago I made that mistake. We had just moved into our new home and wanted to amend my clay soil to put in a vegetable patch. I had 6 cubic yard of compost and 1 cubic yard of sand delivered. By the end of every growing season, the soil was hard as a rock even after adding fresh compost every year.