Deodar Cedar Needle Drop

[hedgehog79]

We have a very large deodar cedar in our front garden which is dropping a lot of needles. The amount of needles is about 1 wheelie bin full (so I supposed about 2 to 3 cubic meters worth) a month.

 

The tree looked quite healthy last year but this year I've noticed the tips of the branchlets at the top of the tree are all browning and this does extend downwards throughout some but not all parts of the tree. It also seems to be carrying a lot more deadwood.

 

I understand that these trees routinely drop needles but what is a healthy sort of level? Is there any way that I can reduce the quantity of needle drop? I'd really appreciate some guidance.

[Le Sanglier]

We have a very large deodar cedar in our front garden which is dropping a lot of needles. The amount of needles is about 1 wheelie bin full (so I supposed about 2 to 3 cubic meters worth) a month.

 

The tree looked quite healthy last year but this year I've noticed the tips of the branchlets at the top of the tree are all browning and this does extend downwards throughout some but not all parts of the tree. It also seems to be carrying a lot more deadwood.

 

I understand that these trees routinely drop needles but what is a healthy sort of level? Is there any way that I can reduce the quantity of needle drop? I'd really appreciate some guidance.

 

Pictures would help, are the areas of browning towards a particular area of prevailing wind? can you see any large silken nests in the canopy?

[hedgehog79]

Hi,

 

Thanks so much for your reply. I took some photos this evening which are attached. When I've looked at it again the South and West sides are pretty green with odd bits of browning. The main browning is on the North and East sides from the canopy through to the branches at the bottom.

 

The prevailing wind direction is South/South West, we live on the coast quite close to the sea so it's quite fresh/breezy.

 

I looked through the camera lens and some binos but I couldn't see any large silken nests.

 

I did name all the files but just in case

 

1st image is 2 weeks needle drop this time of year - in the winter it was much worse.

2nd image is the tree size.

3rd and 4th are needles browning on the south side

5th image is a closer view of the tree from the north side.

 

Thanks for your help.

Edited May 31, 2012 by hedgehog79

[Tony Croft aka hamadryad]

that tree is in trouble, drought stress for one, needle drop and die back is probably related to the lack of permeable surface! no mycorrhizea ect, lift as many slabs as your willing mulch and try to get some agaricus augustus fruit bodies to innoculate the rootzone

 

or watch it die in the dry weather.

[RobArb]

What's the site history?

 

Sent from my Galaxy S2

[Tony Croft aka hamadryad]

also look out for Phaeolus schweinitzii fruit bodies indicating decay.

[hedgehog79]

Thanks, I'll have to google some of those names!

 

We bought the house last jan and at the time I didn't really notice this level of browning through last year. It seems to be getting quickly worse although the needle drop was really bad all last year too. The previous owner planted the tree I think in the 50s and put the slabs down to control the drop. Is this what you meant by site history?

[RobArb]

Yes, exactly:biggrin:

 

You can usually (not always) get/give a better diagnosis when the site/topographical history is know, so things like

 

When were the flags put down, what's happened to the roots, has the soil levels ever change, has there ever been salt damage?

 

There are many questions we can ask, these are just a few.

 

Keep us all informed:thumbup:

 

Sent from my Galaxy S2

[MATTMOSS]

Like what has been said above, I would take a large area of the flags up, get a good layer of mulch down around it and get the hose pipe out and give it a good watering.

Then keep your fingers crossed.

good luck

[hedgehog79]

A little more on the site history. I can't be sure but I think the paving slabs were put down in the last 7-10 years as nothing will grow below it with the needle drop. Also the upkeep/maintenance was quite hard for the old man who lived here before us.

 

I don't know about the root system. The soil pH at the base of the tree is 7, I've been testing all round the garden for other planting. I can't be sure if this has ever changed but rhododendrons and camellias grow very well in this area so I think the soil in the area in general might be prone to slightly acidic.

 

There was another Deodar Cedar in the garden, within about 10m of this tree, which was felled 3 years ago due to poor needle retention and stunted growth.

 

I don't know if the tree has ever suffered salt damage, but the tree is within about 65m of a salt water harbour but I don't know if this would affect the ground water?

 

Thanks for all your help.

[Tony Croft aka hamadryad]

A little more on the site history. I can't be sure but I think the paving slabs were put down in the last 7-10 years as nothing will grow below it with the needle drop. Also the upkeep/maintenance was quite hard for the old man who lived here before us.

 

I don't know about the root system. The soil pH at the base of the tree is 7, I've been testing all round the garden for other planting. I can't be sure if this has ever changed but rhododendrons and camellias grow very well in this area so I think the soil in the area in general might be prone to slightly acidic.

 

There was another Deodar Cedar in the garden, within about 10m of this tree, which was felled 3 years ago due to poor needle retention and stunted growth.

 

I don't know if the tree has ever suffered salt damage, but the tree is within about 65m of a salt water harbour but I don't know if this would affect the ground water?

 

Thanks for all your help.

 

 

the slabs are its biggest problem, changes like laying a non permeable soil covering take at least ten years to show up, this makes me even more sure it is your slabs that are killing the tree. If the tree was planted in them from day one not so much damage would be done by it, but change soil regimes around a mature tree is a recipe for disaster.