AusBonsai

hi everyone,

we have a couple of chinese elms that were going great but lately random leaves are turning yellow then fal off at the slightest touch. does anyone know what causes this?

If it's not recently repoted then I guess- lack of water. If this is the case then water and fertilize it well and it will be fine. My chinese elm just have a new set of leaves thanks to the recent rains in the area.
Cheers.
DK

it is well and truly watered and fertilised. i gogled it and got mixed advice. some say too much water causes this issue, some say its just a normal thing elms do.

My guess would be too much water

G'day mate,

Elms are also susceptible to aphids - which is not likely at this time of year.
However, they are also susceptible to spider mite - which, at this time of year, is very possible.

If there is a presence of spider mite - the only thing on the market that I can think of is a product called "natrasoap" - be sure to follow the directions. If you are able to get your hands on some "kelthane", which is extremely hard as the product was banned a few years back, it will fix the problem in an instant.

To help prevent the incidence of spider mite - always wet the foliage of your trees with cold water - particularly in hot dry conditions. Be mindful not to do this of an evening that is warm and still, as this could cause fungal issues amongst your foliage, it is better done of a morning.

Regards,
Leigh.

while we are on this topic, any ideas on how to force them to push some new shoots? i defoliated and cut back quite hard on mine and its been a fair while since i did that and not even a glimpse of looking like it is gonna grow, like its gone into a dormancy period?


jamie

Tend to agree with Lee re: insect attack. I have been getting a small green aphid on random elms in the nursery the last month. Very small on the under side of the leaf 4-5 aphids suck the goodness out of the leaf it turns yellow and then they move to a fresh green one.
Get a piece of paper under a branch and give the leaves and branch a brush and see what falls out onto the paper. Adjust your eyes as the aphids are green and tiny.
Good Luck Mase

jamie111 wrote:while we are on this topic, any ideas on how to force them to push some new shoots? i defoliated and cut back quite hard on mine and its been a fair while since i did that and not even a glimpse of looking like it is gonna grow, like its gone into a dormancy period?


jamie

Mate not sure about that. I defoliated all my elms like two weeks ago, 6 days later the buds are starting to pop, all are in full leaf again now. Cutting back quite hard should of triggered a heavy flush of new growth especially with elms in general they respond well to this provided it was healthy b4 you did it. How much sun is it getting? They do slow down in summer when it gets real hot but it proberly should of responded by now. How long ago did you cut it back?

cut back about 6 weeks or so ago now, i have lost the top section, (apex took three years to build, its gone) and am probably gonna have to make a new chop on it to where the live wood is again, back to stump. it could be stressed due to some carving i did do to it?


jamie

The other thing to keep in mind Jamie after defoliating is over watering. The tree will not consume much water after its leaves have been removed. Check the roots for signs of rot.

Cheers,
Leigh.

i did that this after noon it doesnt look like a major prob ( maybe a little?), i am thinking of repotting it anyways, that will be the best way to check aswell, would you go full shade again after this or into part sun?


jamie

I would say filtered, or dappled sun for this time of year up your way mate.

Cheers,
Leigh.

Astroboy, could we get you to upload some pics so we can better diagnose your tree and take away a bit of the guesswork . Are you talking about older leaves towards the interior of the tree or new growth?

Cheers
MM

Mojo Moyogi wrote:Astroboy, could we get you to upload some pics so we can better diagnose your tree and take away a bit of the guesswork . Are you talking about older leaves towards the interior of the tree or new growth?

Cheers
MM

Now that is a good idea, that way you are sure to see what is what.

Cheers Pup

Astroboy, have you been using pesticide?
Elms do not like systemic pesticides.

Regards Gerard