I never saw leaves crack like that. Did you look under the leaves for bugs? Possibly spider mites. They are hard to see without a 10x magnifying lens. If you have a bad infestation you should see some webbing, kinda like a spider's threads. They will attack any plant. Do you have a county extension office nearby that you can take a leaf of each plant to?

Please post a picture of the entire plant, in part because it's important to know which leaves are affected & how the rest of the plant is doing.

If just the older leaves, it may be the normal end of the road for them.

"Cracks" such as in the image -- if that's what you're concerned about, aren't important. Further, likely to be mechanical damage.

These pictures were taken on the 8-30-2011

Here is a link that might be useful: {{gwi:111098}}

These were taken on Sept 7th.

Its only getting worse. I have tomato plants about 6 feet away that are starting to get the discoloration as well. The leaves on the tomato plant that are affected are the ones closest to the squash plant.

It all started with the center plant and is now working its way out.

I am desperate to figure out whats going on here as to date, my 3 squash plants only have one fruit each. Its really frustrating.

I appreciate the help.

Narny

Here is a link that might be useful: {{gwi:111099}}

The only bugs I have seen are ants and TONS of them. They dont bite or anything just taking over the garden. I think the lady at home depot called them strawberry ants.

Perhaps nitrogen? Nitrogen deficiency can cause yellowing of the leaves. I'm having some in various "spots" in my new garden where the soil is very challenging.

I dont think this is nitrogen and the reason why is its not spotted... the whole total of the leaf looks like that first picture. The only pictures I have seen that look like these is ones people claim have iron problems. But even then that doesnt match here because its not the new leaves that are affected... its the older ones... and spreading to other members of the genius.. ie tomatoes.

You might be right with your original question.

Once again, there is no location given, but with a zone 9, I'll assume you're in SoCal, AZ, etc, where iron chlorosis is a common problem.

Put a little Ironite around and water it in.

Sue

So Sorry, I am just south of Houston in between Houston and Galveston. Each is 30 min away.

I will give that a try.

Thank you.