Young Fruit trees damaged by weed eater.

I have a fair number of fruit trees I planted last spring in the area I intended to make my permaculture forest. We live in Louisiana where the water is relatively plentiful and the sun is all the time. Our grass is near impossible to defeat. I keep making mulch collars but the grass happily moves into over and over again. Later in the past year, Augustish, I had a baby and delegated all forest care to my husband for that time until Winter. During my Spring pruning I recollared the trees to find that my husband hat hit some of them with the weed eater And apparently sometimes would bump all the way up to them with mower, rather than weed at the bases. In his defense, it is hot as something here in August and September, and I am sure he wanted to spend as little time out there as possible. But now I am worried about my trees. I figured they survived until pruning, which I did in Feb, so they might not be in immediate danger of just dying. But none of the plum trees which were most afflicted bloomed. They are dwarves and the dwarf apples and cherries did bloom. Should I be worried about that? Now, my superior plum tree has put on leaves but has not put on growth since the spring started, unlike all the other trees even those others wacked have put on at least a foot of new growth on all branches. Any advice for someone to make it up to her trees so they aren't stunted after the fact of injury? I can only seem to find how to's on not wacking them and then wound treatment. I think I have passed those concerns at this point.

Since you just planted the trees last spring, it's not unusual that some are not flowering or growing more slowly than others. It's hard to know whether that is due to the bark damage or just getting established after planting. I've seen a plum tree 90% girdled by weed whacking and still grow and fruit surprisingly well.
If you want to boost growth on some trees, try foliar feeding with compost tea sprays.

If you look at the tree and it's 100% girdled anywhere, it will die. This can be tricky, because during leafy time it will look fine (nutrition flowing from leaves ok), but when it tries to feed from the roots in Spring, it won't go.

Prevention is best - don't do that!

If it's already done, you can save the tree with a "bridge graft" which takes one or more strip of bark and grafts over the girdling. This can be done in Winter or very early Spring. Google "bridge graft" to see some images and basic steps.

A plastic tube or cutoff soda bottle or milk jug can make a good longer term protector for mice and weedeaters..

Eric Thompson wrote:
If it's already done, you can save the tree with a "bridge graft" which takes one or more strip of bark and grafts over the girdling. This can be done in Winter or very early Spring. Google "bridge graft" to see some images and basic steps.

I've attempted this myself, but all the grafts failed and the trees died anyway. My damage was not from a weedeater, but mice. I first cut out the damaged sections to make a straight cut margin parallel to the ground. I then tried to "bridge" the gap with bark taken from branches of the same tree. This contrasts completely with my very successful whip grafts when cloning named varieties.

In my personal experience, I'd say if they are still just young trees, just dig them up, throw them out, and start over. In my own orchard, trying to revive injured trees just means you have a patheticlly weak tree limping along much more slowly than anything surrounding it.