Nice walnut tree with secondary trunk

[IL80]

I have a nice 20" dbh walnut tree growing that also shares a common base with about a 12" secondary trunk. The secondary trunk is growing out at an angle and has some nasty knots in it. Should I cut off this secondary trunk? Will this help the main tree? Couldnt get my photo to load sorry!

[beenthere]

You should be able to cut the small one off and it won't make a difference either way to the large one. Some risk of rot entry, but not much more whether the small one stays or is removed.

[drobertson]

agree, probably not worth the risk of disease,  but if it has to go, then there's not many options.

[IL80]

Okay, thanks..I will leave it then. I just thought by removing it, maybe the main trunk would benefit.

[Sprucegum]

The 12 is stealing moisture and possibly some sunlight from the 20. I would consider these factors when predicting the future and ship that Dang 12'er to Alberta!  ;)

[mesquite buckeye]

Anytime you remove a trunk that big you are taking a chance that you will allow entry of organisms that will start rotting the butt log of the better trunk. If you wait 10-20 years to cut the main trunk, you are asking for it. Just sayin'.

If you were removing the larger of a pair of trunks and both trunks are decent, the smaller trunk benefits from the large root system that is already in place and will quickly refill the canopy opened from the removal of the larger trunk. In this case the chance for a faster grown log may outweigh the risk, especially if the split is at ground level. You may only have rot damage for a couple feet at the butt and otherwise a decent log in 10-20. ;D

[Phorester]

The main problem is inhibiting sunlight to the canopy of the good quality trunk.  Taking soil moisture and nutrients away is very minor, but since both trunks share the same root system, taking one away would allow all of that to be used by the trunk that was left. If the poor quality trunk is at least 4 feet shorter than the good quality trunk, I'd leave it. The taller trunk is taking sunlight away from the shorter trunk. If the poor quality trunk is the same height or taller than the good quality one, I'd remove it.

Rot in a cut stump starts quickly at the top of the stump and progresses downward into the remaining stump and into the adjacent trunk. Rot from the side of a stump takes longer to progress into the stump. But if the poor quality trunk was cut at ground level, it will still take years for the rot to progress into the other trunk.

When do you plan on harvesting the good quality trunk?  If the poor quality one is competing for sunlight, you might want to cut it, say, 5 feet above ground.  It would still remain alive, would probably re-sprout, and would just rot at the center from the top down. This would remove the sunlight competition and greatly inhibit rot from traveling to the good quality trunk for many years.  Although your friends would think you were crazy to leave that high stump  ;D

[Okrafarmer]

Nice analysis, Phorester. 

[IL80]

All of the analysis is appreciated! I'm in no hurry to harvest this tree and would love to watch this walnut turn into a 26 or 28 incher someday. This tree along with about 3 others that are 15-16" dbh are growing in a flat creek bottom with oak timber on the adjacent hillsides. The 12" secondary trunk is growing out at an awkward angle and is full of knots so I was thinking that it will never be a marketable log but what do I know! It definitely is not grabbing sunlight from the main trunk. Just trying to optimize this tree, it's by far the best on the property.

[Okrafarmer]

Well if you do cut it off (and I'm not saying you should, necessarily), cut it at an angle to where rain fall will run off it instead of soaking in, and also seal it with some kind of sealing agent. Like the tar they use for pruning fruit trees or something. (Anybody else can correct me if I'm wrong).

[Phorester]

Cutting the stump at an angle for water and snow to run off is definitely a good idea, Orkafarmer.  I wouldn't be concerned about using any wound dressing. Two schools of thought on those, (TRanger for one likes them ;o) but my thinking is that research says  these are not necessary at best, and at worst can be detrimental. One reason being that they can crack around the edges allowing moisture to get in underneath it which then does not dry out since it is between the sealant and the top of the stump (or branch if you're pruning those), away from sun and wind.

This is orchard country here - several thousand acres of commercial orchards - and they do not use sealants when they prune their orchards.

[Okrafarmer]

Ok, that's good enough for me!

[Magicman]

I had a "sucker" to sprout out from my old Pear tree which apparently was from the graft root stock.  This tree had been hidden from view for many years and the sprout was nearly as large as the Pear tree trunk.  I sawed if off because my thoughts were that the sprout was stealing nutrients from the Pear tree.  That was about 18 years ago and today that side of the Pear tree is hollow.  I only wish that I had found it and trimmed it off when it was small.