Rick Shory

Offering a little something you might not otherwise have

sleeves around stem and post


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Metal sleeves keep raccoons out of fruit trees.

Aluminum sleeves they cannot climb past will keep raccoons out of your fruit trees.


Raccoons are in practically all urban and rural areas. They can destroy crops of grapes, cherries, plums and other fruit, knocking down and ruining much more than they eat. A barrier raccoons cannot climb past is a simple preventive.

I first heard of this idea as putting “stove pipe” around fruit tree trunks. The metal is too slippery for animals to climb, and too hard for them to dig their claws into. However, modern fire regulations have made sheet-steel stove pipe largely obsolete, and therefor nearly impossible to find. Also, stove pipe is limited to a few sizes (diameter), and steel rusts in the rain. Here, I describe how to make the equivalent from aluminum roof flashing.

Flashing a width of 20 inches is convenient. It comes in 25-foot rolls.

label

Label

When you use it for sleeves, there are two general cases, pictured below. You may be putting it around a plant stem such as a tree trunk or grape vine (as on the left), or around the post of an arbor (on the right). When around a post, it’s a good idea to use two lengths, because a determined raccoon can sometimes shinny up past one!

sleeves around stem and post

Stem (left) and post (right)

In either case, a detail of screw placement is helpful. A tidy and logical placement would be one screw at the top, one screw at the bottom, and maybe one in between. But raccoons are agile animals, with dexterous tiny “hands”.

A screw at the bottom may be all the toehold it needs. Two screws only at the top, spaced a few inches apart, holds the metal into a sleeve just as well. It’s not quite as tidy, but a raccoon climbing from below finds only sharp edges and slick expanses.

diagram

Two screws only at the top works better

For cutting the metal, it’s handy to unroll the flashing on something soft like cardboard, so it doesn’t get all dented up. Temporary weights, such as blocks of wood, can hold the metal flat for easy marking. A convenient length to go around a 4-by-4 post, or a slim trunk or vine, is 17 inches. Around a stem, this will serve for several years. Finally, the stem will grow too thick, and you will have to replace the sleeve by a bigger one.

metal roll on cardboard

Cushion metal to prevent dents.

Cutting with tin snips, there will be an awkward point when you are almost through. It helps to bow the metal up along the line you are cutting.

cutting metal

Cut metal with tin snips

For putting the two sleeves on a post, you want to overlap the upper over the lower, so as to give no toeholds. Not the single sleeve picture below! The upper one is only temporarily in place to show how to measure.

upper sleeve 20 inches

Upper sleeve temporarily in place

Mark your post at the bottom edge of where the upper sleeve will be. For flashing 20 inches wide, this will be that distance (20 inches) below the top of the upper sleeve.

marking a post

Mark the bottom of the upper sleeve

With the upper sleeve gone, mark about 4 inches above the previous mark. This 4 inches will be your overlap.

marking the overlap

Mark 4″ above the bottom of the upper sleeve

Put on the lower sleeve first. In this case we have tied a length of old bicycle inner tube to hold it there until we can place the screws.

sleeve tied with rubber

Sleeve held in position by inner tube rubber.

If you put the screws within the overlap, there is no possible way they can serve as toeholds.

sleeve screwed to post

Sleeve on post using two screws

Placing the upper sleeve with the seam on the opposite side of the post makes it harder to climb. Our investigation of how a coon can get past a single sleeve is not conclusive. Night cameras don’t always give the best image. But the raccoon evidently does it by a “bear hug” around the post. It may have been a particularly enterprising raccoon first figured this out, and then others learned. A second sleeve, which bells out slightly, and has the rough edge on the opposite side, has so far been enough to thwart the raccoons’ shinny-up technique.

both sleeves in place

Uppers sleeve in place.

To put a sleeve around a sapling or vine, it helps to assemble it first. Then, the screws will all be there, with their guide holes ready. Start by shaping the metal into a cylinder. As shown below, you can hold it for further work using vise grips.

It’s possible to punch the screws through the metal directly, using self-tapping sheet metal screws; but it’s easier if you pre-drill the holes.

drilling holes

Pre-drill screw holes.

Then, insert the screws. Screws #4 x ½” are big enough. Now you can take the vise grips off and the cylinder will stay in shape.

screws in sleeve

Screws hold sleeve together.

To get the cylinder around the stem, you have to take the screws out. Again, a section of old inner tube rubber is helpful for holding the sleeve temporarily closed while you fit the screws back in.

sleeve tied with rubber strip

Rubber strip holds sleeve for screw positioning.

Hanging the sleeve loose and dangly both gives the stem room to grow, and makes it harder to climb. The sleeve does not weigh much, so one wire is enough support.

sleeve around stem

Screws back in place.

Wire 14 gauge is plenty strong. To anchor the wire to the sleeve, curl one end of the wire into a small loop. Loosen the top screw a few turns and hook the wire loop under it, then tighten the screw back.

hooked wire end

Wire end curved into a hook.

The wire can be as long as needed. If you are sleeving a grape vine, you can hook the upper end of the wire over part of the arbor.

wired hooked on arbor

Upper wire end hooked on arbor.

If you are sleeving a tree, you can hook the wire over the lowest limb. It can be loose; the sleeve is not going to jump off. There is no need to twist the wire around the limb, and risk strangling the branch as it grows.

wire hooked over tree limb

Hook wire loosely over tree limb.

A loosely dangling sleeve like this has thwarted raccoons, and even most squirrels. You would have a hard time climbing a greased pole, but you might be able if motivated enough. Think how much harder to climb up over a swinging bell.