16 votes
Accepted

Is this heavy blue-green growth on my tree trunk and branches a form of lichen?

These look like the tree lichens that are growing on my own trees. A lichen is a composite organism where by a fungus lives together with an algae in a symbiotic relationship. They don't hurt the tree,...
Graham Chiu's user avatar
  • 23.1k
14 votes
Accepted

Should trees be staked when they are planted?

Should all trees be staked when they are planted? First, you have to find out Why people stake trees. What benefits are there to staking young trees? In nature, trees can germinate, grow, and mature ...
J. Musser's user avatar
  • 51.7k
10 votes
Accepted

Dwarf Apple tree in heavy clay

Apple trees do well in clay. There are a few things you could do different next time: do not put stones or other soil amendments in the bottom of the hole. If the planting hole has reached the clay ...
kevinskio's user avatar
  • 58.8k
10 votes

How should I save an oak tree wounded by ground root removal?

I had a large (massive) Elm tree that had all the roots on one side cut about 6 feet from the tree due to an idiot plumber running a sewer pipe. This was a deep trench, too. I used an in-ground ...
TreeMan's user avatar
  • 101
10 votes
Accepted

How should I care for a young cherry tree?

When you say 'recent', if that means within the last year, the only thing you need to do is keep it well watered during dry spells for its first 2-3 years. Hopefully you dug the soil over well and ...
Bamboo's user avatar
  • 132k
10 votes

Any way to save a large tree that's starting to split/crack down the middle?

Consult a tree surgeon. If you want to save it, it might be possible to cable the top parts (not "tie a rope around") to keep it from spreading wider. Depending on the decay of the trunk, this might ...
Ecnerwal's user avatar
  • 23.2k
10 votes

Pruning a weeping mulberry

Oh my goodness. Do you understand the treasure you have? Find a master pruner to create a covered walkway! How wonderful. If you destroy this tree I will haunt you when I am dead! (Grins). That ...
stormy's user avatar
  • 40.2k
10 votes

Very few needles on lower spruce branches

I live in a region where Norway spruce grows wild, and in my experience, the lower shaded branches shedding their needles and dying is perfectly normal for these trees. For the tree, there's no point ...
Ilmari Karonen's user avatar
9 votes
Accepted

How should I care for my multi-variety apple and pear trees?

You definitely need to do some pruning. Before you start pruning a tree, you should find all of the graft points. Since you have multi-graft trees, there should be one graft at the point where each ...
michelle's user avatar
  • 9,464
9 votes

Is this heavy blue-green growth on my tree trunk and branches a form of lichen?

As Graham says they are lichen and moss. A tree will commonly live in a symbiotic relationship with millions of macro and micro-scopic organisms. In tropical and temperate rain forests overgrowth on ...
kevinskio's user avatar
  • 58.8k
9 votes

Any way to save a large tree that's starting to split/crack down the middle?

Yes, a professional arborist could save the tree using cabling and bolts as the practical Ecnerwal illustrates. This would be something you would do as soon as possible. It appears that the two ...
kevinskio's user avatar
  • 58.8k
9 votes
Accepted

Does moss harm the tree it grows on?

Moss will not harm the tree! Good news indeed because the forests around here would be in BIG trouble! Moss does not have true roots - their "roots" are just for the purpose anchoring themselves to ...
Tyler K.'s user avatar
  • 1,719
8 votes
Accepted

What are the best practices for keeping trees healthy in a construction area?

This answer will be based on a tool from the University of Georgia Cooperative Extension Service Forest Resources Unit. I have changed it somewhat over the time I've used it, but I was sure to make it ...
J. Musser's user avatar
  • 51.7k
8 votes

What do nurseries feed their potted trees to make them so healthy?

Bear in mind that many commercial outlets do not actually grow trees in pots, they simply buy them in from a specialist supplier. The actual supplier will raise the saplings under controlled ...
Bamboo's user avatar
  • 132k
8 votes

How can I protect my plants from cows and goats?

You need to build a fence, or a wall.
Ecnerwal's user avatar
  • 23.2k
8 votes

How can I protect my plants from cows and goats?

You will have some difficulty (at least from goats). There are a few solutions I'm aware of - Kill the goat(s) - Its the only way to be sure. Put goats on a chain or in a run (arguably more cruel ...
davidgo's user avatar
  • 3,579
8 votes

Harm a tree by trimming top/exposed only part of root in lawn?

Evil Elf asked in a comment about studies of what does happen to trees when root work is done. A survey of web links shows that root pruning is commonly given as good advice. Academic studies of the ...
kevinskio's user avatar
  • 58.8k
8 votes
Accepted

Is this rule of thumb for timing dormant pruning correct?

I think the grouping would look more logical if it were made on the way the trees set fruit: stone fruit trees (plum, apricot) are the early bloomers, while the trees with fruits that contain seeds (...
Alina's user avatar
  • 5,406
8 votes
Accepted

Should I redo this pruning cut?

The cut is fine but the tree has or will have issues. You can see that there is already interior decay in the heartwood of the tree. As stormy indicates water will enter the wound and decay will ...
kevinskio's user avatar
  • 58.8k
8 votes

Should I leave fallen apples (windfall) to rot under the tree?

According to this publication from the University of Wisconsin Extension, the larvae of several destructive insects can grow to maturity in windfallen apples: Apple Maggot Flies (pp. 12, 14) Codling ...
Jurp's user avatar
  • 18.6k
7 votes

What do nurseries feed their potted trees to make them so healthy?

I'm pretty sure they don't give them anything initially, although if the tree does not sell within a few months, I imagine they would give them slow release fertiliser appropriate to the plant - ...
davidgo's user avatar
  • 3,579
7 votes

Any ideas on what is wrong with this tree?

Yes - you violated the prime directive of tree health Don't change the soil level around a mature tree (especially - any tree, really) by more than an inch (up or down) or you'll probably kill it ...
Ecnerwal's user avatar
  • 23.2k
7 votes

Treating tree disease that manifests as warts/galls/bumps on leaves

I can't tell what tree that leaf has come from, so it's difficult to identify precisely the cause of the galls on the leaf. Regardless, the vast majority of gall growths like this do not cause harm to ...
Bamboo's user avatar
  • 132k
7 votes

Is my maple tree beyond saving?

First get an arborist, one who is familiar with your locale and can have hands on expert examination. It is obviously an old maple. Everything declines before it dies of old age but while it ...
stormy's user avatar
  • 40.2k
7 votes

Is it better to cut off drying branches sooner or later?

This is the correct place to ask this question. The answer is yes, pruning branches that aren't doing anything for the plant saves the plant energy. The plant will 'prune' itself eventually so if we ...
stormy's user avatar
  • 40.2k
7 votes
Accepted

Liquid Amber/Sweet gum (Liquidambar styraciflua) tree stress and rotting

This type of occurrence is called a split due to a weak crotch and two competing leaders. The split has been inevitable for many years, and was just waiting for the weight of wood on one side or the ...
Colin Beckingham's user avatar
7 votes
Accepted

What is this white foam under my tree?

If this foam has appeared only during the heavy rain you've been experiencing, its a natural phenomenon. It occurs because some trees contain chemicals in the bark which can cause a soap like foam as ...
Bamboo's user avatar
  • 132k
7 votes

Can I substantially reduce the height of a large holly tree?

You can reduce the height by up to half, but if you do, it will grow in an ugly shape afterwards. Holly tends to apical domination, meaning it gives a good approximation of a pyramidal shape if left ...
Bamboo's user avatar
  • 132k

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