River Birch Questions...

[ChrisWNY]

I have a fairly healthy River Birch in my backyard that is now in its 3rd season, and about 20' tall with a 10-15' spread (when purchased, it was barely 4' tall with a 3' spread). It's growing out of control, the lower branches are getting so large that they droop near the ground, especially when wet.

There seems to be a lot of conflicting information out there regarding when to prune River Birches - I've read that pruning should be avoided May 1 - August 1 (due to birch borers), but also avoid pruning over the Winter because the branches "bleed" excessively. I've also read that a Birch bleeding out is no big deal and part of the healing process. Which of the schools of thought is correct? Well, when can I prune this thing -- March 14th at 1:47AM, but only if the moon is full and there is > 30% cloud cover (LOL)? Any advice would be appreciated.

This tree also seems quite temperamental - we had a warm, dry second half of May out here in Western NY (near Buffalo), and my River Birch dropped quite a few leaves, as soon as the heavy rains hit in early June (we've had nearly 6" of rain so far in June), it started growing quickly again. Should I simply plan on unloading gallons of water around the root zone whenever dry weather hits? I pretty much live in a swamp, otherwise known as a flat, poorly-draining, heavy-clay soil piece of property, when it rains, the layer of clay under the topsoil creates a flat-out bath. I thought this tree was native to the Southern US, so I'm amazed that some heat up here in the tundra we call Western NY would phase this tree.

 

[S Mc]

Well, when can I prune this thing -- March 14th at 1:47AM, but only if the moon is full and there is > 30% cloud cover.

You got it, Chris.

It seems to me that the birch family will get more diverse recommendations due to regional differences that any other tree species.

Here, we are very careful to trim only during the times that the bronze birch borer is not active, and we also won't trim a birch in the winter, as any warm day the tree bleeds. And I mean BLEEDS. COPIOUS amounts of sap pour out of the wounds until the buds swell in the spring.

Between those restrictions you do feel that your optimum window is very limited.

The Betula nigra, River birch is native from Massachusetts to Florida west to Minnesota and Kansas. But this habitat is restricted to stream banks and other moist places. (Dirr)

So it is going to like fertile, moist, periodically wet, but well-drained areas. And they are listed as a moderate to fast grower.

The fact that your tree is growing very well leads me to think it is very happy in its circumstance. However, a fact that could accentuate a positive to the point it becomes a negative would be fertilization. Is this tree being fertilized either for itself or in conjunction with a turf care regimen?

Before you start trimming, please post pictures. Birches can be particularly unforgiving when pruned incorrectly.

Sylvia

 

[ChrisWNY]

I fertilize my lawn a couple of times per year, a light fertilization in late Spring (in May), and I put down a more moderate dose in the Fall, during early September, so I'm sure the trees pick up some of the lawn fertilizer. I only use the balanced stuff (slow release nitrogen), generally 15-15-15. I do fertilize my trees separately in the very late Fall after dormancy has set in (November), using a balanced fertilizer. Since most of my trees are constantly under attack by pests (Jap beetles, gypsy moths, etc.) during the Summer, I treat every tree with Bayer Advanced in early Spring before bud-break, so I guess that counts as fertilizer as well since Bayer includes it in their systematic tree/shrub treatment (which supposedly lasts a full year).

Here are some photos showing how quickly this River Birch has grown over the past 3 years. At the bottom of the Year 3 photo, you can see some of those branches (left side) that droop near the ground. I figure if I don't clip them at some point, the deer will just annihilate those branches over the Winter.

Year 1: Just after planting, before my lawn was around...

Year 2: Lawn is in, River Birch is growing fast, nearly 10' tall...

Year 3 (Taken Today): Looking like a tree now, about 18' tall (that's a young Swamp White Oak in the background, planted it at the same time, it's about 14' tall)...

 

[ChrisWNY]

Any ideas on pruning this thing (based on the photos above)? Just wondering when I can cut those lower branches that droop onto the ground especially after a rain.

 

[treeseer]

get your mulch right first. it is too deep on the stem and not out wide enough. recommend mulching out to the branch tips and forget about pruning until late summer.

o and btw just because the species grows near rivers does NOT mean that it needs or even likes moist soils. like elms and willow oaks and and this species is favored for urban areas because of low oxygen requirements.

but yes they do shed leaves if allowed to dry out

 

[ChrisWNY]

Thanks, treeseer - do I need to dig out sod or can I just throw the mulch over the lawn, does it matter? I just assumed if I dig out sod, I'll potentially harm feeder roots. The area directly around the stem does not have any mulch on it, I much at least 6" away from the trunk, just difficult to see from the camera angle.

 

[ChrisWNY]

Ok, I more than doubled the size of that mulch bed under the River Birch, used the weedwhacker to scalp the area of lawn where I expanded, then laid down cardboard on the scalped grass, and finally threw about 2-3" of mulch on top of the cardboard. I must say it does look a lot more aesthetically pleasing, and the tree no longer dwarfs the bed area underneath. I don't plan on ever expanding it any further, that Birch better figure out a way to root into the lawn area or deeper into the soil, because I'm not expanding that mulch bed again any time soon. It certainly seems large enough now, took 8 big bags of mulch to fll in the expanded area. I pulled mulch away from the trunk of the tree, there was only a shallow layer near the trunk, nothing major. I never mulch right up to the trunk, usually a small layer washes itself into the stem area on its own, I know all about the harm that "mulch volcanoes" can cause.

The wife was pushing me to put some edging around the bed, but I didn't want to chop up any shallow feeder roots with an edging shovel, I am trying to convince her that the best option will be large rocks or something surrounding the bed that will just rest on the ground rather than protruding into it. Unfortunately I ran out of time to dig into the Red Maple root flare, tomorrow is another day...

Here are updated photos, I edited this post to include photos taken during daylight during the morning...

 

[treeseer]

nice job; it does look lots better.

borders are nice but require edging. yes rocks (or anything) above grade is good, digging to install is not so good.

 

[Mighty Oak]

River Birch

You are so very lucky to have your tree growing. I planted one last Fall and it never leafed out so they gave me another one and it did have leafs braking out on it and than in a few weeks the leaves dry up , but the tree is not dead for I can bean the limbs without them braking off.

What is going on here?

 

[ChrisWNY]

Need more details about where you're planting it (photos are always the best description). Ohio typically receives a decent amount of rainfall, so my best guess is that your River Birches were planted too deeply in the ground, which was why they declined. The other possibility is soil condition - have you had your soil tested? If the pH was way off, that could cause problems also, but it's more than likely a planting depth issue.

 

[Mighty Oak]

River Birch

My soil has a PH of 7. Just how deep do you plant them? I planted it a few inches below the surface, I did not think it was to deep. Will it come out of it? I was thinking it was stress. I give it a fertilizer Spike from JODE, it was for acid loving trees.

Yes we have had allot of rain this year, and I would think that it would have taken off.

Just what do I need to do to get this tree to grow?

 

[treeseer]

Just how deep do you plant them? I planted it a few inches below the surface, I did not think it was to deep.
Just what do I need to do to get this tree to grow?

Replant it this fall, the right way.

http://www.treesaregood.com/treecare/tree_planting.aspx

 

[ChrisWNY]

As treeseer already stated, you'll need to replant. The root flare of the tree should, if anything, be planted ABOVE grade. Nearly all trees require decent drainage, though the River Birch can tolerate wetter soils, it won't thrive there like it would in a well-drained situation. Because my property is nearly flat and poorly-drained, I've had to plant nearly all my trees on mounds, we're not talking volcano-like mounds, these are more gradual mounds that protrude a few inches above grade that prevent water from drowning the roots. You may need to do the same in your situation in Ohio. Do not bury the root flare underneath soil, it must be left exposed above the soil. Keep mulch at least a few inches away from the trunk as wet mulch that is in contact with the trunk can cause decay and rot.

 

[StihlyinEly]

Year 3 (Taken Today): Looking like a tree now, about 18' tall (that's a young Swamp White Oak in the background, planted it at the same time, it's about 14' tall)...

There's certainly room for debate, but I wouldn't thin/prune this tree at all for a few more years. All those leaves are furiously adding to the strength/expanse of the roots, and I'd allow that to happen for another three or four years, at which point the tree will be wonderfully established. And it won't be too tall to be effectively pruned/thinned with pole pruner or pole saw.

Plenty of time then to take out branches growing/rubbing against other branches, growing back in toward the trunks of the trees, etc.

 

[ChrisWNY]

Thanks for the input, my biggest concern is the tree becoming too large to safely prune, but I'd rather allow it to maintain its vigorous growth than snipping new growth which might hinder root development. I trimmed some of the smaller inward-growing branches during the late Winter, no bleeding sap issues afterward. I'll leave it alone from here on out, at least for a few more years.