I have a tree as seen in the above pics, an approximately 65-year-old Rainier Sweet Cherry tree. When I bought this house it was overgrown and full of lichen and moss.
I was told by an arborist that the best thing to do was to remove excess branches to open up airspace in the tree. I did this, removing almost 1/3 of the bulk of the tree, about 2 years ago. Since then I believe the lichen and moss have gotten worse.
Other suggestions to restore the tree have included spraying it with poisonous Cupric Sulfate or Iron Phosphate... But I don't want to spray poison all over the rest of my garden!
Is there any organic thing I can do to get the lichen and moss to die so that the old tree can thrive again? It still produces fruit but I know the tree can be healthier.
Or, has the tree simply reached the end of its lifespan? This tree is, historically, one of the first of the Rainier Sweet variety and I don't want to lose it.
I'm not certain this info's accurate, but a very experienced arborist told me that lichen and moss are not harmful to a tree. If fact, they may be helpful in that they provide a slightly more acidic environment on the tree's bark which discourages growth of infection and infestation by insects. Maybe look more at the roots/ base of the tree. Does it have a well with nice mulch kept back from the trunk? Or is it overgrown with weeds and (gasp!) grasses? I think that those things would be a more likely suspect. Good luck with your lovely cherry! But don't use poisons or chemicals please!
Are there other symptoms that make you think the tree is unhealthy, besides lichen and moss? I've also been told that lichen/moss are not harmful.
If you are just looking to increase the yield and quality, then judicious pruning, spreading compost, and clearing weeds from the root zone are useful. You could also consider some companion plants.
If pollination is a problem, put up a mason bee house.
I have a neighbor three plots down who raises honey bees and all my flowers seem to get pollinated without issue. If anything the issue is that the cherries fall off the tree before they are ripe, are eaten by birds, or are simply too high up to harvest, since this tree has exceeded the 50 foot maximum height these trees are supposed to get to.
When I moved in the tree had weeds and grass right up to its trunk, I have since removed the grass and put in a well with alder bark mulch, which seems to be working. The crotch of the tree was soft, but it has improved since I pruned the living hell out of it 2 winters ago.
I can certainly prune more... But I will probably need to rent a cherry picker (pun intended) and continue the pruning up into the 60' bulk of the tree.
So lichen and moss are not evidence that the tree is unhealthy? I have a couple apple trees also, probably about the same age (further research puts this tree at about 60 years old, since the variety was created in 1952, and this house was built in 1947). Anyway, the lichen and moss on those trees is worse... Almost a carpet, and the apple trees no longer produce fruit. I have been thinking of removing them... But don't want to kill them if they still can be brought back from the edge.
Considering the age & height of the tree, I don't think that pruning it now, especially in the top half, will produce the results you're looking for. I can't clearly see the whole tree from the ground up in the pic, but it doesn't look like it has been pruned into a low-branching orchard style tree in its past. If you start removing a lot of wood from the top of the tree, you will be signing up for climbing up there every year to remove hundreds of water shoots, not to mention just stressing out the tree. If there are huge dead branches threatening to fall down on something however, definitely get rid of them.
I'd agree with Patrick's recommendation: adding lots of compost and companion plants, It will just help to strengthen the tree and prolong it's (still probably rather short) life. As for the birds.. free poop for your garden!... and for the tree for that matter.
I'll also throw in my opinion that lichens are not a bad thing for a tree...
As for the moss... do you ever have any irrigation sources hitting the tree, or is it just wet where you live? I've seen trees that have been pounded by sprinklers with very aggravated fungal symptoms.
You could always plant some cherry pits, and experiment with grafting whips/buds from the old tree once the seedlings are big enough. Then you'll maybe get another 60 years out of it!
The apples: do they show evidence of a history of regular pruning? eg. lots of old branch scars or an 'umbrella' type shape? If so, they would fruit better if returned to that shape. If no, same recommendations as for the cherry.
If your research is correct regarding the age of all of these trees, fruiting naturally declines as trees reach the end of their life span. However, as the trees actually begin to die, you should see abundant fruiting in a last desperate attempt at procreation!
careful pruning your cherry anymore, pruning cherries tend to make them overreact in growth the next year, and also makes them more susceptible to fireblight. and agree with the others, lichen isn't generally harmful. By itself, it certainly is not. the only thing I've heard of is that it can serve as habitat for pests that might hurt the tree. but not worth working so hard on.
as far as birds on a cherry that size? man, what can you do? Ive always wanted to chain a housecat in the tree, see how that would do....
Time is mother nature's way of keeping everything from happening at once. And this is a tiny ad: