I don't technically think such a thing exists -- the vining "zuchinni" types you mention are not Cucurbita pepo like regular zuchini, they are cultivars of C. moschata, and if allowed to grow to maturity will develop into a butternut type squash. Any yellow summer squash I know of are cultivars of C. pepo and are bush form. Probably the closest you will come is a vining variety of C. maxima or C. pepo with pale colored fruits which you could harvest very young. Banana squash (not the bush types) and sweet potato/sweet dumpling type squash come to mind as possibilities. One year, I planted banana squash,and couldn't understand why they weren't setting any fruit. Come to find out, my mother thought they were summer squash and kept picking them for zuchini, and I kept eating them without knowing it. Over the years, I've found out that virtually ANY type of squash, whether C. pepo, C. moschata, C. mixta, or C. maxima, makes a fine zuchini if picked young enough. Perhaps someone else will know of a vining form summer squash for you.

I have a decade of experience with growing crops without irrigation and little or no fertilizer, which is effectively what is being talked about here. If we are going to throw in lack of full sun on top of that might as well not waste one's time. What I have learned is that it's all about the crop species and timing. Crops that can establish in some kind of self-perpetuating perennial cycle give far better yields than ordinary annuals. Deep-rooted to boot is very desirable. Parsnips are perhaps the winner, IME. Walking onions would be ideal for this "wildcrafting". Well-adapted annuals that self-seed precociously and don't cross with close wild relatives are quite good, notably red russian kale and red mustard (in climates with mild, damp winters). Carrot is a problem because it does not compete well with weeds and won't seed true in most areas because of QAL. Wheat is a good choice because it does most of it's growing in the fall and spring when there is more likely to be rainfall. Harvesting is very difficult, however. Rye is a bad choice due it's allelopathy if you have anything trying to germinate in springtime. Corn, of all the common annual crops is by far the best IME. As noted, deer tend to leave it be, animals the will ravage ripe sweet corn don't bother grain corn, it tolerates summer drought pretty well, and drought is less of an issue in little-disturbed ground. Squash, IME often does very poorly in a non-irrigated condition. It must be direct-seeded (which goes for all crops that will not be irrigated). If you get lucky with rainfall you might get a decent crop. It does grow pretty well in coarse fresh ground if highly fertile. I usually have problems with deer and other varmints gnawing at the fruits and browsing foliage. In a survival situation I would put a lot of grain corn out in freshly-cleared dry-land areas, with beans inter-planted later. Almost all other staple crops - potatoes, squash, carrots, sweet potatoes, etc, I would keep close to home for irrigation and protection from animals. This would be assuming there is no time to waste on likely failures.

Tulle rocks. If you have vining cucurbits, you can actually keep them in a line, under several yards of standard 52" width tulle. The stuff is cheap. Actually, you can bend the vines around so you have two parallel strands of vines as they grow. That's a nice way to fill up the space available under that width of tulle. That's what I've done this year. If you have more vertical and bushing squash (e.g. zukes), you may have to sew some widths together to fully contain the plant. Of course, don't do this in an area that was infested in SVBs last year. You'll just seal them in. You will probably have to pollinate manually, but here's a hint. Don't pollinate a female flower with a male flower from the same plant. That's called "self" pollination, and in general is not a good thing (as in, inbreeding). For recessive characteristics that are undesirable, inbreeding hurts. Yes, many plants self pollinate within individual flowers (e.g. nightshade family), but that isn't optimal.

I'm having the same problem Planetes is... my squash plants have a couple of wide open female flowers right now, but all of the male flowers are tiny and undeveloped, they don't look like they are even close to opening. And the thing is, my plants are heriloom varieties, not some kind of new hybrid watzit as far as I know. Like P said, the season here has been very cool (it was below 70 this past weekend! But it will be in the 90s this weekend and for a few more weeks.) and I am afraid I have planted them too late. In addition to this, they are in a rather shaded area, and only get maybe 6 hours of direct sunlight all day (I tried to tell my wife it was a bad idea to plant them there, but she would rather plant them than toss out the extra transplants we had). I'm guessing that the plants have a deficiency of some kind- either weather is too cool, the soil lacks nutrition, or the plants are just not getting enough light.