Oak leaves dropping- what to do?

[Judy Landau]

We live in southern Michigan in a reconverted schoolhouse next to a large wooded area with many mature maples and oaks. For the past four days, many of our maples have been dropping (raining) green leaves that seem brown only at the place where the leaf meets the branch (the petiole?) How should we go about addressing this problem?

 

[treeseer]

(raining) green leaves that seem brown only at the place where the leaf meets the branch (the petiole?) How should we go about addressing this problem?

Yup, the leaf's "stem' is called the petiole, and the leaves seem to be abscising. Please post pictures and give details about the site and its history.

 

[Ekka]

Hi

Could you please let us know what town you are in, I've tried to do some rainfall stats research and working on Lansing it appears to be a rather dry year.

After the wetter and cooler winter period trees put on a lot of foliage for spring/summer season. If there's a hot dry spell trees can shed some of the foliage ... but close attention has to be paid to the leaves being shed, if there's no sign of disease such as spots,chewing, fungus/webs etc it could be a natural response for the tree. The shedding you have described is at the natural abscission zone of the petiole, the tree's preferred place, so if the leaf appears healthy it may be that there isn't enough stored energy, water and nutrients to support an overgrown lush canopy ... natural thinning.

Good health and vigor is the answer, trees have a good chance of fighting off problems if they're healthy. I don't know if it's practical to water, organic fertilize and mulch if you are talking about a forest or large area.

It sounds like the condition is common to most of the trees so it's more likely to be a climatic response.

I found some links that may help you out, check these.

http://www.mortonarboretumphc.org/f... or Develop Early Fall Color August 2002.pdf

http://web1.msue.msu.edu/msue/imp/modzz/00001706.html

http://cahe.nmsu.edu/ces/yard/1997/030397.html

And yeah, a picture is worth a 1000 words. Pics of the area, soil, etc help to.

Keep us posted.

 

[Kneejerk Bombas]

Do the leaves look like this:

http://images.google.com/imgres?imgurl=http://www.ppdl.purdue.edu/ppdl/images/maple_petiole_borer.jpeg&imgrefurl=http://www.ppdl.purdue.edu/ppdl/weeklypics/Weekly_Picture5-7-01-3.html&h=450&w=600&sz=29&tbnid=e97lehBHIS0J:&tbnh=99&tbnw=132&hl=en&start=1&prev=/images%3Fq%3Dpetiole%2Bborer%26hl%3Den%26lr%3D%26sa%3DN

 

[Judy Landau]

Not really. Leaves were green when dropping and the leaf stem (petiole) looked almost burned about two inches drom where it attached to the leaf- it has stopped now and seems to have been the maple petiole borer- Have no capability to upload picture-
Thank you and all for the help

 

[Judy Landau]

Ekka- we have had drought conditions from midMarch to mid-May, rainfall normal now but totals still below season average- wasn't drought but the maple stem borer- stopped now - Thanks for your help -Judy

 

[JeffE]

It's from the maple petiole borer, a sawfly (type of wasp) with larvae that bore into the leaf stalk of sugar maples. Although the leaf drop can appear alarming, it's generally not enough to seriously harm the tree, and in most cases no control is necessary.

See this site:
http://www.uky.edu/Ag/Entomology/entfacts/trees/ef405.htm