This article has been updated from its original text.
Late winter is pruning season in many orchards, with dedicated gardeners eager to get out the orchard ladder and pruning tools to begin this first chore of the new gardening season. But before you begin, it is advisable to brush the cobwebs off and inspect the tools, especially the pole pruner.
A brief ‘pre-use’ inspection of the pole pruner head will ensure a more efficient cutting action as well as a safer tool for the operator. If the nut holding the pivot bolt has worked back a few turns, for example, the pruner will still work but the cutting blade will shear to the side with each cut, resulting in ragged cuts which take longer for the tree to heal. If the cord is worn even in a single spot it could break when under stress, throwing the operator off-balance. This is particularly hazardous since pole pruning is often done while perched atop an orchard ladder.
1. Check cord anchor-point for signs of wear.
The double-braided nylon cord supplied with most pole pruners will last for years if stored under cover during the winter months. And while the cord may appear to be in good condition, there is one spot where it receives maximum strain and may not be visible at first glance. Look at the end of the cord where it is anchored to the pulley housing and see if there is any fraying. If the outer layer of nylon is torn, consider either replacing the cord or cutting it at this point and advancing the line a few inches so you can tie a new knot.
Heavy-duty pole pruners may have a double-pulley system. Follow the cord to where it dead-ends on the second pulley and examine for signs of wear. Some pole pruner models have a short length of chain which runs through the pulley, with a ring on the end of the chain for securing the cord. Check the cord at the ring for signs of wear, and examine the chain for any rusted or worn links.
2. Inspect spring for rust.
Most pole pruners have a 2-inch spring at the head which retracts after each cut, leaving the mouth, or hook, of the pruner open to receive the next branch to be cut. The ends of the spring should be sufficiently through the eyelets on the pruner head and cutting blade. Assess the amount of rust on the spring – if any part of the spring appears stiff or rusty, now is the time to replace it. A new spring only costs about $2 and should last for many years if the pruner is put away over winter.
3. Be sure the nut holding the pivot bolt is tight.
During normal operation, the cutting blade assembly can take a lot of wear and tear. Some branches are difficult to reach or are at an oblique angle to the cutting head, so the blade slices through at an angle which stresses the pivot bolt and its holding nut. Also, other branches may bear against the nut, poking it from any direction. Over time, this nut can work loose and back off. Take a moment to check that the holding nut is secure; if you can move it using your fingers, then take small crescent wrench and tighten it.
4. Clean out the blade slot in pruner head.
With each cut while pruning, the cutting blade goes through the branch and enters a slot in the inside of the ‘hook’. Small bits of green bark and stem fiber can build up in this slot and, after months of storage over winter, can dry and harden. Even a small bit of impacted material will prevent the cutting blade from making a complete cut, resulting in ragged cuts which may take two or three passes to complete. Use a nail or pick to scrape out this slot and take a close look to be sure it’s completely clear of debris.
5. Inspect cord for any frayed spots.
The pruner cord may appear to be in good condition, but run your hand down the full length of the cord to check for any worn spots. Even a relatively new pruner may have damage in one spot on the cord where it might have snagged a branch spur, tearing a bit of the outer layer of nylon. If the cord is torn or worn anywhere, it should be replaced to ensure operator safety.
A pole pruner is often used with the operator perched atop an orchard ladder. When the pruner is fully extended and the operator is reaching out while pulling the cord firmly, any sudden break of the cord can upset the user’s balance and cause him/her to fall from the ladder. We’ve had this experience in our own orchard, which reminded us that pruning, which appears to be a safe and simple job, can indeed be hazardous!
6. Inspect the cutting blade for chips or cracks.
Pull the cord to advance the cutting blade so you can get a good look at it. Inspect the cutting edge for any obvious chips or nicks, and look at the sides of the blade for any hairline cracks. It’s easy to disassemble the blade to dress any small nicks with a file, but it’s advisable to replace worn or damaged blades. A new cutting blade only costs about $12, but be sure your replacement blade matches your pruner head. It should be from the same manufacturer since the specifications for these blades varies with different brands.
It only takes a few minutes to thoroughly examine the pruner head for safe, efficient cutting. In our experience, there’s usually something that needs repair or adjustment. Pole pruner manufacturers offer replacement parts or replacement ‘bundles’ which include new cutting blade, cord and spring. You’ll enjoy pruning your fruit trees, and the cuts will be cleaner, once you’ve ensured your pruner is in good operating condition.
