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Squash Melon Cucumber leaves Yellow Dying spots

I've been giving out answers like the ones I quoted below whenever someone asked about Squash / Melon / Cucumber leaves with Yellow spots and patches or Dying brown spots and patches for a while now.

Today, I found the same yellowed spots and brown/dying patches on a few squash leaves and each one I turned over was crawling with multiple hatching event squash bug nymphs on the underside. Yes, I used duct tape to catch them.

So far I have already been finding most of them at egg stage so these nymphs were from either eggs I missed when removing or from those dribble trails of 1/2 dozen or less eggs they sometimes make.


Similar minor marks or fully wilted smaller leaves are also indicators that the adults are somewhere nearby. I caught about a dozen or more today by following those clues. Crumpled up leaves are also worth investigating. Squash bugs, leaf foots or spotted cucumber beetles were hiding inside. It seemed like the spotted cucumber beetles had caused more damage than Striped ones or wilted leaves according to what I saw this morning.

Subject: Diseased Cucumbers turning white, then dying
applestar wrote:Where are you located? If somewhat in northern location like me and just have had some summer thunderstorm systems blaze through, then you may be looking at same as these -- stinkbugs. Squashbugs, and leaf foots, as well as cucumber beetles. My garden is experiencing a sudden influx of these pests since last week to a few days ago. Typically they start with the squashes, then melons and cucumbers.

Subject: What do these leaves mean?
applestar wrote: ...
Another thought -- I'm kind of suspicious that the yellowing could be aphids or other sucking pests under the leaf. ALWAYS look under the leaf if anything seems to be wrong.

The spots are early blight or septoria or other leaf disease. Cut them off. The tomato will grow more leaves every week. But if really concerned about stripping them naked, just clip the leaflet with the spot until you see spots on entire branch/leaf, then cut the entire thing off before the infection moves into the main stem.

Cucumber and squash -- my experience has been that those light colored spots followed by wilting is indicative of stinkbugs and squash bugs, leaf foots, too. They are either mating and dining before laying eggs -- you will find adults and possibly eggs -UNDER THE LEAVES- :wink: or a hatching event has taken place and you will find a bunch of nymphs. Either way, GET RID OF THEM. I "snatch, throw on ground and stomp" the adults and clip off the leaf (it's a goner anyway) fold over the nymphs and ... yep stomp on them. ....hmmm.... I guess on the deck you may not want bug and leaf juice all over the nice wood.... well, have a container of soapy water ready and drop them in.

I hear duct tape works great for catching them, too. I plan to try that when I start seeing them in quantity.
Subject: Zucchini, Squash and Cucumber Leaves Dying!
applestar wrote: ...
Also, inspect the underside of yellowed and wilted leaves for cucumber beetles and squash/leaf-foot/stink bugs (and egg clusters, too). A fair % of those yellowed and chewed up leaves seem to follow egg-laying activities and hatching event :evil:

(Yeah, I DID'T happen to cut off this leaf in the way I described, but this is a solid stem C.moschata so not as critical) I sometimes squish them on the leaf if only small numbers, but with a bunch of them like this, find it easier to cut off the leaf and grind it into the ground under my gardening bootheel. :twisted:

These bugs are slow and easy, but cucumber beetles are quick to scuttle and fly off so be ready to catch them. :?

Subject: Applestar's 2017 Garden
applestar wrote:Last night we had a pretty severe thunderstorm. Typical weather pattern so the system came up from southwest.

... I noted a TKKx leaf with squash bug eggs and Striped and spotted cucumber beetles in Melon and squash blossoms.

I got the trusty duct tape and started for the eggs, but saw cucumber beetles on the way, and, on a whim, put the duct tape over the blossom -- they are quick and most often scuttle and fly off -- hard to catch, but it turned out that the duct tape can catch them by the hard shell wings. They also try to fly off and think they are clever when they land on the duct tape and then start walking funny on the stickynsurface, but if you are quick, you can squish them against the adhesive and they get stuck.

Then I saw squash bugs mating on the melon trellis. That made me look closer and they were everywhere -- or at least three pairs. Duct tape was handy for catching them, too. They do release their stink once they realize they are stuck though (Blecch)

Getting back to the squash, I got the eggs off of the TKK -- of course majority of the eggs were on the OTHER side of the fence trellis... two more pairs of squash bugs... a few juvies probably from stray eggs I missed... then noticed that what I feared had happened: There was a leaf pressed against the insect netting from the inside and and a squashbug had laid an egg cluster through the netting (top-left photo) --


-- another duct tape to the rescue! Also shifted the vines and leaves away from the netting and further inside while I was in there.

I will really need to keep an eye on the melons now. I had been expecting to find squash bugs and leaf foots on them because someone -- maybe toxcrusader -- had reported them on HIS melon trellis one year... and have been looking, but these were the first ones I have seen. But now, I'm sure there will be more.

Melons are setting fruits. Image
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Re: Squash Melon Cucumber leaves Yellow Dying spots

Hmmm, so those critters on your duct tape are squash bug nymphs? I would've thought they were spiders and left them alone! I'm always so surprised at how many nymph stage bugs do not look like their ultimate adult selves, if that makes sense.

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