how and when to reduce willow + mimosa

[tree-fancier123]

Hi,

a gardening customer has the type of willow that makes spirally branches, he says people sometimes dry out the spirally branches and paint them for interior decorations in a vase, hope that is enough to id it.

Also a mimosa.

The mimosa is getting big and he wants it reduced in height and spread. A reduction cut on a branch back to just above any side branch, so that becomes the new leader is what I was thinking for most of it. On a mature mimosa (20+ yrs) would taking a whole limb out cause decay. I'm not up on all the technical bits of how each species compartmentalise decay. Is there a rule of thumb for mimosa, eg is a 50% reduction going to kill it? I know they say dont remove the branch collar, but if there isn't much of a colar is say a 10mm stub from the trunk about right?

With the willow it has been previously pollarded, maybe not correct term, but new spirally growth cut back to 'knuckles' He has previously had it done in the winter nov/dec when bare - do willows suffer from being cut back when the sap is rising and can all new growths be cut back to the previous knuckles? (and what is the term for these knuckles?)

thanks

[Tom10]

Your 'spirally' willow is a Contorted willow. They are often heavily reduced / pollarded and take this treatment well (as most willows do) if it is done correctly. I would suggest to reduce all of the growth back to the knuckles with clean cuts using secateurs / a sharp hand saw every couple of years. Don't leave stubs but don't also cut into the knuckle itself. I would suggest anytime from about November to March as an ideal time - I dont think you would cause it too much harm doing it now but if its not causing anyone any problems then you could just leave it until this winter.

 

In regards to the Mimosa Im not a buff on these and have little experience with them... I dont know about other arbs on here?... I found this online

 

'This fast-growing, deciduous tree has a low branching, open, spreading habit and delicate, lacy, almost fern-like foliage. Fragrant, silky, pink puffy pompom blooms, two inches in diameter, appear from late April to early July creating a spectacular sight. But the tree produces numerous seed pods and harbors insect (webworm) and disease (vascular wilt) problems. Although short-lived (10 to 20 years), Mimosa is popular for use as a terrace or patio tree for its light shade and tropical look'

 

In reference to your pruning cuts question you are correct, you need to cut to the branch bark collar or branch bark ridge - the collar is usually easy to see, and the ridge you simply need to cut perpendicular to the branch angle and mirror image the angle of the ridge itself - leaving it stubby is bad practice and flush cutting is just as bad. Its minimum standards to get these cuts correct. Obviously this is a brief and fundamental guide and knowing where to aim your saw when target pruning comes with experience! theres no 10mm rule of thumb, some collars are tiny and some several inches into the branch dependent on species / previous work etc.

 

If in doubt contact a local Arb on here, and subcontract the work out? Im sure someone is in your area...

 

Good luck.