What's wrong with my Red Oak?

Our red oak is very yellow instead of healthy green like our neighbor's red oak. Any idea what's wrong? Any suggestions to "make-it-all-better"?

A closer pic of the leaves...

Most likely an iron deficiency (chlorosis). Could be manganese deficiency if your soil is alkaline. You can get a product called Ironite at most any place that sells garden supplies. It's cheap and takes care of iron deficiency. The manganese supplement is harder to find. Some swear by common black strap molasses, applied as a drench at about 3-4 oz. per gallon of water. You can check with your county Extension Agent. They usually have the best advice for their area.

Thanks Hoosier. I had wondered about chlorosis. Some of the leaves (all on one branch) are also shriveled up and dying. Is that also a symptom?

Yep, it can eventually kill the tree. You could also acidify the soil by adding sulfur and/or aluminum sulfate. This will help the tree absorb iron and manganese. Good luck.

Best of all, make sure there's a good area at the base of the tree that is mulched, not lawn. At least a metre radius, preferably 2 metres, from the trunk. Put down a 5-10cm thick layer of composted leaves over this area.

Resin

HG - I've read a research paper by Ohio State University that reported that adding iron to the soil actually makes less manganese available. We have experienced some manganese deficiency problems here with Acer rubrum used as street trees that were planted in alkaline soil. ( Not my doing!) Some of the trees were replaced and some have been treated with manganese spikes. The web link is the only source I've been able to find. I'm not endorsing the site. Your suggestion to contact the Texas County Extension is something I strongly urge. They can give nbgard information on how to get a soil test. With a soil test determining just which nutrient is missing and Resin's prescription for annual mulching to improve the soil naturally, the tree should do well in the future.

http://joa.isa-arbor.com/request.asp?JournalID=1&ArticleID=1445&Type=2
http://www.treehelp.com/itemdesc.asp?ic=TR-PAL-FMn

http://www.co.comal.tx.us/EXT.htm

Lot of great info! Thanks to all. I will set about seeing if I can save this baby!

Good point Snapple45. I think the latest research leans to not so much a iron deficiency as the manganese, and I'm glad you located a source of manganese spikes, which I had not been able to find! Also, the Texas tree might be a Southern Red Oak, which might have different needs that the Northern Red Oak, so it's best to contact an Extension Agent. Thanks for the info. It's so great that the DG community can help each other!

It's not Southern Red Oak(Quercus falcata)(wrong leaf shape, texture, bark, etc.). It looks like Texas Red Oak (Q. buckleyi, previously Q. texana), which would be a bit surprising since Texas Red Oak is tolerant of alkaline soils. Which would point to a mineral deficiency in the soil it's planted in, rather than just an alkalinity problem. It's also possibly a Pin Oak(Q. palustris), but from what I can see in the photos it doesn't match as well with Pin Oak as it does for Texas Red Oak. Nurseries in Texas are notorious for lumping Shumard Oak, Texas Red Oak, and Northern Red Oak all together and simply calling them "Red Oak". It wouldn't surprise me if they've done the same with Pin Oak, simply calling it "Red Oak". Either way the advice given above is the proper advice no matter which exact species of Oak that has chlorosis.

I'd doubt it is due to mineral deficiency in the soil, more due to poor soil conditions (most likely soil compaction and associated drainage problems, caused by heavy construction machinery) restricting the ability of the tree to root well into the soil and pick up the nutrients. If the soil was mineral deficient, the other trees in the area would also very likely be in the same state.

A good mulch will encourage worm activity in the soil, which will help alleviate soil compaction and improve drainage. Skip the manganese spikes.

Resin

Chlorosis is very common to certain tree species (most notably red maples and pin oaks) in areas with alkaline soils. I've seen many cases where a single tree in the same vicinity of others of the same type get chlorosis and respond to treatment successfully. It's amazing how soils can differ just within a few yards. However, it's always good to encourage good soil structure and micro-organisms through proper soil preparation and (most easily) organic mulch. I've seen many trees respond to iron and/or manganese supplements. Sometimes though, it's better to avoid planting susceptible trees in alkaline soil areas.

Regardless, be sure to let us all know what you decide to do, and what happens!

This message was edited Apr 22, 2009 8:37 AM

Even more good info. Interestingly enough, this tree was healthy and green last year. It has just become yellow this spring after applying some tree fertilizer that was recommended by a guy at the tree nursery where we bought a Drummond Maple. Makes me wonder if the fertilizer did something. Anyway, I have been amending the soil around it with rabbit manure, decomposed mulch from last year, coffee grounds, etc and have mulched the top of the bed with bark mulch. I have already discovered some worms in the soil and added a few to it myself. Looks like the soil test is definitely the route to go at this point. We do have heavy clay on top of caleche (sp?). I know I haven't amended out as far as the drip line since the bed is not quite that large. This tree was here when we bought the house 2 years ago and has not grown very much compared to our neighbor's tree. Yes I have tree envy...

Thanks again to all. I'll keep you posted on results.

Tonya

The fertilizer adds a twist! Do you have the bag? If so please list here the exact composition.

I'll see if DH still has it, I bet he does. He is also going to call that tree nursery guy and quiz him about it.

With trees planted in areas of high construction levels (like housing developments) there's no telling what's underneath the soil surface. So, it's quite possible there is something there which is causing this chlorosis. It's also possible that the tree was root bound and poorly planted(circling, damaged, and otherwise "bad" roots weren't corrected and no roots were loosened and spread out from the root ball). The tree in question doesn't look too old and it often takes several years for problems at planting time to show up. Construction debris, rocks, etc. causing subsurface problems can even take a decade or more to show up. So, it's quite possible for any of this to be going on. Unfortunately, even a soil test won't tell you what's underneath the tree and surrounding soil, so most often times these problems aren't found out until the tree is being replaced or dug up. The soil test though is the first step you should take. It will definitely tell you if there are any problems with the soil itself(rather than any buried debris).

If you could take a close up of one of the twigs and buds as well as the leaves both top and bottom, I could give a positive ID on your Oak. Because if it turns out you have a Pin Oak and it's planted over a caleche subsoil it will never grow well and will require constant treatment to just keep it alive. If on the other hand your Oak turns out to be a Texas Red Oak, then you have a much better chance of possibly correcting this problem, because Texas Red Oak is capable of growing in alkaline soils, although not severely alkaline.

Thanks kman, I'll try to post some more pics by tomorrow.