Forestry Mulching

[purlsnponies]

Hi guys!

Part of my property is a little “forest” of small invasive trees with live oaks scattered around. I’d like to clear out the invasives, and my plan was to first do basal bark (or cut stump) applications of herbicide on the invasives, followed up with forestry mulching a few months later.

Arborists and extension agents are warning me that the oak roots are so shallow that they’ll be damaged by the mulcher, so I should keep the mulcher out past each oak’s canopy. But so many of the “before and after” forestry mulcher pictures show beautifully cleared spaces with oak trees left standing. I’m confused!

So, I’d love to get opinions from people who have actually had this done, or considered and rejected it.

Have you selectively cleared around oaks? If so, how close to your oak did you mulch? How deep? Did it turn out to be too close?

Were the dreaded 1-2" “spikey stumps” a problem after forestry mulching? Were you able to maintain the area with a tractor after mulching without worrying about tire damage? Can you ride a horse through the area without fear of tiny pokey stumps?

Thanks for any experiences you can share!

[Simkie]

I have no idea what the answer is, but do note that those pics are probably shortly after the work has been done. Who knows how those oak trees look a couple years down the line, or after a bad windstorm. If the extension guys and tree guys are both warning that the mulcher will damage your oaks, it would be worthwhile to listen to them.

[purlsnponies]

@Simkie

I have no idea what the answer is, but do note that those pics are probably shortly after the work has been done. Who knows how those oak trees look a couple years down the line, or after a bad windstorm. If the extension guys and tree guys are both warning that the mulcher will damage your oaks, it would be worthwhile to listen to them.

Thanks, Simkie! You’ve hit my main concern on the head. The extension agents and arborist are all young guys and I don’t know that they’ve ever actually even seen a forestry mulcher in action, though… which made me turn to the wonderful people here!

Last year, I cleared out a patch of this ‘forest’ by hand - handsaw and herbicide. The oak that I uncovered was gorgeous. (And then it fell on my septic drain field. ) But, I’m willing to do it all by hand if necessary.

[goodhors]

If the stubs bother you, you might do a heavy mulch layer over them of bark mulch so they don’t stick up visibly. Surround the Oak in the mulch, which should help prevent regrowth of brush and not damage the shallow roots. You don’t say if this is in horse pasture where stub removal would be more important than just landscape trees. Mulch and stubs will breakdown over time, though it might be a longer time depending on what kind of stubble shrubs/trees they were.

We have been cleaning old pasture fence rows of brush here. They have not been tended in about 20 years, so brush covered lots of ground out into the field, with big cedars and dead trees in the shrubbery mix. It is rewarding to see the entire tree once all the brush and vines have been removed! Some are lovely specimens against the skyline, showing the now exposed trunk and branching. Young trees coming along will have the benefit of better sunlight and no competition for nutrients. Sure is slow going though. I think we have enough brush piles to have one or two burning all winter. No danger of fire escaping us then. I will be using a tractor rotary tiller for our stubble removal. It has done a great job in several places we cleaned up with no big trees to worry about the roots. It really works up soil, stubble has not slowed it down. But we plan to plant grass for hay, so not going deep. There will be a “farm lane” along all the fence lines to drive on, so tree roots will be minimally disturbed during the tilling for stubble removal. Just mowing the grass after that.

Our trees are hardwoods. There are various kinds of Oaks, White, Red, Burr Oak. Hickory, some in the Elm family, a few Red Maples I want to come down. I have planted a couple Dawn Redwoods and a Yellowwood, which is a flowering native tree to add diversity, on the open side of field. Shade the farm lane as they grow. Been watering them daily during our recent drought, they drink a lot! May add some Tulip tree saplings I am encouraging to get bigger.

Good luck with your projects. Gardening on a BIG scale makes you feel good.

[purlsnponies]

Oh wow, goodhors - your property sounds beautiful! It has to be so rewarding to see the transformation, and watch the trees flourish. Thank you for your message!

The area I want to clear is within one of the pastures, good question. My arborist suggested that I chainsaw out the stubs if they’re that much of a problem. Which terrifies me, but I guess I can don all appropriate safety gear and give it a go. Sure wish I had a tractor!

[Simkie]

Can you get references from the mulching guys? People who have had that work done in an area similar to yours, preferably a couple three years back?

Another guy to talk to–if you can dig one up, not sure how easy it would be–would be an insurance claims guy. I know that sounds totally nutso to suggest, but the guy we had here after a huge storm was just a total WEALTH of info about how trees fall down. He talked at length about how water oaks had really shallow roots and just toppled right over with strong enough winds. I think that’s the type, anyway…most of what he said was really over my head. (But he did stress that not all oaks are the same, and there’s some type with shallow roots that is just really prone to damage…)

[purlsnponies]

Ah, those are both brilliant suggestions Simkie! Thank you!

[B_and_B]

Part of the confusion between the advice and the pictures may be the type of oak involved. Some of the northern oaks have deeper root systems and wouldn’t be bothered. The live oaks may have a more shallow root system. Up here in CT, I would be wary of using heavy equipment around a sugar maple, white oak, or american beech; but would be willing to get a lot closer to a black or red oak.
That being said, there are several different types of mulchers: some leave stumps, some cut to ground level, and some can get several inches into the ground.
In any case, you want to make sure it is not going to leave a stump. We call them punji sticks at my work, and they can be just as ugly as the original punji stick which is a sharpened, lethal, booby trap.

[purlsnponies]

Good points, thank you B and B! The live oaks do have fairly shallow root systems. The mulcher that this operator would be using goes 1/2-1" below the soil surface.