Lilac bush and peeling bark from maple tree

(Question)

lilac bushHi, there.

I have a few gardening problems I need help with.

I have a lilac bush in the backyard that was planted over 13 years ago. Every year it blooms and has been bushy and healthy. This year in the middle of the bush the branches were empty of leaves and flowers but the top produced flowers and leaves. I suspect it is getting too much shade – but I don’t know if this really is the problem. Right next to the bush is a fir tree and I also have two maples trees in the backyard. Should I trim back the branches back to the base? And when would I do this?

Some of the bark is peeling off my maple tree. Is there something I can do to help the tree?

Thank you so much.

(Answer)

Hi,

Some of your tree issues are related, and some may not be. I will take the maple (Acer sp.) tree issue first:

Like all trees, when young, the bark is usually smooth with little ‘barkiness’ – strips, knobs, rough patches, all which help identify the tree in its later years. It may be that your maple is maturing, and beginning to get its grown up bark.

On the other hand, there are some things that may affect the bark of a tree to cause odd bits. One, is wildlife. Squirrels, some birds, chipmunks, insects, and, don’t laugh, people. For some reason, a hanging piece of bark is too tempting for people to leave it alone, and off it goes. For the animals, they have food related reasons. The mammals like the taste of some bark, or there has been a shortage or their usual foods. The birds may be looking for insects in a crack or tear of the bark. The insects are usually a beetle, and bore a hole in the bark to the cambium layer and lay eggs. The larvae are what causes the damage, and the other wildlife looking for them, may damage the bark further.

Secondly, natural or mechanical damage. The latter could mean the bark has been scraped by a mower, vehicle, or even a badly wielded shovel; the cut or tear can be an invitation to the above noted wildlife. Sometimes, an improperly pruned branch, whereby the cut branch has been accidentally dropped before the cutting was completed, tears the bark in a strip. Natural damage could be from sun exposure or frost cracks. Sometimes on young trees particularly, the south facing side of the tree is heated up by the sun; the freeze/thaw action can crack the bark and cause loosened bark or strips.

If you have checked and see no insect damage, the tree will likely heal itself by callusing the affected area. Bark paints or tars are not recommended. Further information: https://ask.extension.org/questions/137816

As for your mature lilac (Syringa sp.),  your thought that light conditions seems correct. The shrub is reaching high for the light to produce flowers. Although the centre of the shrub should at least have leaves, it is not surprising that flowers have not been produced on the lower branches. If you look now, you will see the thick buds forming at the top of the shrub – those are next year’s flowers, as they are formed throughout the summer, and lay dormant until May or June the following year rolls around.

You ask if you should prune the fir (evergreen) and the maple to allow more light. I cannot tell from the photo if this is the most prudent response. It may mean ‘limbing up’ the maple to a point where its branching is too high. If it may mean removing a couple of branches flush with the trunk while maintaining the natural shape of the tree, thereby increasing the light to the lower branches of the lilac, then that may be fine. Pruning of maple are best while dormant – December to February is best, as the sap ‘bleeds’ once the tree is out of dormancy. Summer works well too.

Pruning the fir is a bit more problematic, especially if it’s just one side. Any way you look at it, it changes the shape of the tree, and not always in a pleasing way. If you think it will add the light you need for the lilac, then pinching the new growth or ‘candles’ can be done in the spring. It should be done in such a way to keep the shape of the tree. Pruning out branches leaves a hole in the canopy of the tree that will not be replaced – another awkward look.

Your other option may be moving the lilac to a sunnier spot overall. Lilac, like may vigorous growing shrubs will respond well to hard cutting back to prepare for transplanting, as it will send out new shoots. This can happen in the spring. Be prepared that flowering will be curtailed, as noted above, the buds are grown the previous year. If this is a viable choice for you, you can look how to do it here: a Toronto Master Gardening Guide: http://www.torontomastergardeners.ca/gardeningguides/planting-a-tree-a-toronto-master-gardeners-guide/ or the following link:

http://www.canadiangardening.com/how-to/techniques/how-to-move-a-large-shrub/a/1549/2