Monday, April 5, 2010
Renewal Pruning
Greetings again during the earliest, warmest and driest spring we’ve had in our 15yrs growing hazels in Wisconsin!
Attached you’ll see some photographs of Mark Shepard performing renewal pruning on hazelnuts. With the bush hazelnuts that we’re growing, some sort of interaction is needed on occasion to keep them producing optimally. Since THIS years nuts are produced from buds formed LAST year, it follows that the more buds we grew last year, the more nuts we get this year. On large, uniform plantings this is accomplished through coppicing… Cutting the entire plant to the ground periodically. The plant then doesn’t produce for a season or two, then begins in earnest once again. We do this on many of our hazels….
Not all of them, however….. Many of our rows of hazels have plants at different growth stages….Older survivors in line with newer replacements. rather than coppice the entire row and set back the younger plants before they’ve really gotten going, we do renewal pruning.
The photos on the sidebar show our 40HP tractor with its 3-pt hitch mounted air compressor. Hooked to the air compressor is a telescoping, pneumatic pruner. From the relative comfort of the tractor seat the operator can renewal-prune dozens to hundreds of hazelnut shrubs per hour. We clip the oldest 3 or 4 stems in the bush, then lay the trimmings in the vehicle alley behind the tractor where they will eventually get ground to chips when we mow later on….
Below I’ve included a description of Renewal Pruning that can be found on the website of Johnson’s Nursery in Menominee Falls, WI (www.johnsonsnursery.com) It is written with the home landscape in mind, but the principles apply to renewal pruning of bush hazels. Common Witch hazel mentioned in the article below is NOT Hazelnut!
Renewal Pruning Benefits
-Plant’s natural form maintained
-Plant’s height reduced
-New growth initiated below each cut resulting in a denser plant
-Old and diseased wood removed resulting in a vigorous, healthier plant
The best time to prune most shrubs is when they are dormant. Just prior to bud break in March or April is the best time, although it can be done anytime during the dormant season. When pruned at the proper time, the cuts readily seal over and new growth quickly arises. If done later, there is less of a response to renewal pruning. Do not prune in late summer or early fall because the new growth will not fully harden off before winter.
How often do you need to renewal prune shrubs?
Normaly, over the life of the shrubs, you should only have to remove a few canes per year.
The benefits can be easily observed on redtwig dogwood. The younger wood of redtwig dogwood is more colorful, while the older, heavier canes are more woody and less colorful. Simply remove the largest diameter canes with the least color at the ground line, leaving behind the younger, more colorful stems. The following season more new, bright red stems will be produced giving the plant more visual impact.
Renewal pruning is very useful on most leafy (deciduous) shrubs. Lilacs, honeysuckles and shrubby dogwoods respond very quickly to renewal pruning. However, it does not work well for all shrubs. Burningbush should never be renewal pruned, while other large-scale, specimen shrubs such as cornelian cherry dogwood and common witchhazel may never require it.
