Don't let that stop you. There's still time to make yourself a DIY gathered end from taffeta tablecloth or ripstop nylon from Joanne's or what have you. You could also head to a REI and pick up an Eno or something. Might even be able to beg a spare hammock from someone attending. It's not going to be freezing and bugs shouldn't be too bad (I get by without a bug net--just wear one of those mosquito net hats). As long as it hangs between two trees, it should be fine.
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