by, 03-01-2015 at 10:11 AM (14362 Views)
Fencing for your retreat needs to be thought out a good bit. Various considerations include questions like:
"Can a vehicle gear into this area readily?"
If that's the case then the post size of the fence needs to be bigger in that particular area, the posts need to be closer together, you need to be sure the posts are in far enough and hopefully set in concrete as well. All these little things making using a vehicle to slug an opening in your fencing harder to do.
Obviously it would be nice to do this the entire way around the perimeter, however it would be cost prohibitive to do that unless it's a small acreage.
First identify choke point areas and natural openings wherein vehicles could pass through, what areas are impassable in the wet season? Where is the hard, firm soil?
We have always be careful when putting in defensive preps that the very inclusion of these doesn't give cover to the BG's.
Herein is where the ideas of putting up big concrete road barriers is a stupid idea. That 3 foot high concrete wall might stop a Mack truck, but it's also going to provide excellent cover to an attacker.
As with everything in retreat design, their is always compromises- time, security, cost factors, etc.
Often times to save some cash, you can look around and find used or new "cull" utility poles. A 35 foot pole can be cut into 5 usable posts with each post buried 3 feet in the earth with 4 foot sticking out. This would exceed engineer recommended "10% of total height plus 2 feet" that is used in burying utility poles for intended purposes. A 7' total length pole = 7.2 inches (10%) plus 2 feet equals 31 inches burial. The hole should be tight and preferably in tough soil. Concrete the post in if possible as well.
I've run trucks and backhoes into posts set in this manner and they have both stopped on a dime. Anyone who has ever ran a small bulldozer knows you get the same effect when you run into a tree stump. Which is why it's often better to scrape around the base of the tree, then attempt to push the tree over with a dozer than cut the tree down and then try to remove the stump and roots with a dozer.
Often times during the clearing phase of putting up the fence, some stumps can be left to the attacker side of the fence to operate in this same manner. Again, consideration needs to be given to the size of the stump, type of wood, etc. First and foremost will it provide cover? OK maybe, but for how long before it rots out? The tradeoff also is while it's fresh and for upwards of a few years, depending on type of tree, etc. it will act to restrict vehicles. Their is large pine stumps from trees we cut in 2008 that still stop a small dozer and backhoe in their tracks when they are ran at with moderate speed.
We want to keep our fence lines clear for ease of viewing from OP's, cameras, PIR type devices, night vision and thermal devices, etc. but it's often a toss up on keeping the opposite side of the fence "too clear." Too much clearing on the opposite side of the fence means easy access, possibly for vehicles, ATV's, large groups of people, etc.
I am currently favoring leaving the stumps, etc. on the opposite side of the fence, with the added extra of clearing the brush around each stump. So you think you found a "sweet spot" from which to observe, fire from? Good, I WANT you to think that. The reality is your now locked in to that position. And by providing some amount of cover FOR YOU, it's now all "marked and 'membered" and on charts in OP's and part of the defensive training to know these spots. These are further covered by any number of early warning devices including seismics, PIR detectors, cameras. In bad times they may be laced with razor wire to deny the use of them or lock you into them. Other implications are best left to the imagination for now
When doing your clearing, again the tradeoff comes between security and utility. In a standard firewood progression we would seek to cut the ugly trees, the ones with cancer, the ones with odd crooks that made them unsuitable for lumber, etc. Here we are looking solely at denying cover. However we can't make it a moonscape. Judicious planning and looking over the "lay of the land" will help show you which trees to cut, which to keep in order to create a "flow" in movement, restrict vehicles, channel and provide as little cover as possible.