I want to put up a swing for my kids and I have 2 trees (approx. 20 ft. apart) where I would put up the main support. 2 16 foot 2x10's overlapped and nailed to the trees.

Am I jeopardizing the health of these trees by doing this?

Reply to post by Paul, on June 03, 2002 at 14:44:08:

Do you honestly believe that nailing anything to trees is a good idea??? No, you will not likely harm the "health" of your tree immediately. Long term however, you could jeopardize not only the health but also the structural integrity of your trees. My experience shows that many people attach many things to their trees, but when they have no further use for them, they do not remove those fixtures or adjust them to accomodate tree growth. Instead of nailing 2X's to the tree maybe you could hire your local certified arborist to inspect the trees and, if appropriate, install a cable between the trees, then hang the swing from that.

James.

Reply to post by James Causton, on June 03, 2002 at 14:44:08:

james is right in saying that nailing into trees harms them. It creates cracks which can be motorways for decay.

Instead you might use bolts. Predrilling with a bit one size smaller will allow for a snug fit without making cracks. The tree will grow around the bolts, swallowing them in time, but will not get indigestion if bolts are installed correctly.

As long as you're putting up a swing, why not consider ercting a larger play structure, integrated with the trees?

Reply to post by Guy, on June 03, 2002 at 23:54:16:

It seems like I've seen this discussion before. Maybe it was another forum.
As for the play structure: be sure to consider the tree roots if making footings. Also, some nice soft mulch may break a fall and also protect some against soil compaction under the swing.

Reply to post by Mark Goodwin, on June 04, 2002 at 08:49:28:

Mark, you are not alone!!! It seems to me that I have been in this same discussion dozens of times. Keep on keeping on,

James

Reply to post by James Causton, on June 04, 2002 at 14:43:04:

It may be an old discussion, but it's still a good one. Structures can be built around trees (think Swiss Family Robinson) safely. It's natural for kids of all ages to be on and around them.

Yes posts need to be sited away from major roots, predrill for bolts, allow for sway, and other commonsense precautions. Once that's done, build away.

Reply to post by Guy, on June 03, 2002 at 23:54:16:

A minor clarification.

Drill 1/16 smaller for LAGS and 1/16 over for BOLTS.

Reply to post by Paul, on June 03, 2002 at 14:44:08:

Hi, Paul. Let's try again here.

Yes, nailing can be harmful to the tree. Cracks, possible decay infections. In a large healthy tree, probably very minor concerns, if only a few nails are used and not too close together. Lag screws or bolts are usually more secure, and if predrilled less likely to lead to cracking.

The biggest problem, as already suggested, is leaving the assembly on the tree a long time. The tree expands with a new layer of wood, increasing its diameter. Eventually it will push against the beams, maybe even growing around them. This causes more damage than the nails or bolts.

The attachments must be planned for long term durability and minimal effect on the tree, or tyou should plan on removing them after a few years. A few calls to local arborists should find someone with a good knowledge of physiology and attachments to the tree. Get some local help to advise you how best to make the swing set.

The International Society of Arboriculture maintains a current list of ISA Certified Arborists. The searchable list can be accessed at the ISA Web site, at:
http://www.isa-arbor.com