Worm-ridden schach

I discovered that there is insect infestation in my schach. I don’t think I’ll be able to buy new schach before Sukkot. Am I allowed to use this schach? (Schach is the material (tree branches, reeds, etc.) that is used for covering the sukkah — the Sukkoth booth.)  

Dear …!

It is forbidden to use insect-infested schach, since the bugs can fall into your food (that you are going to eat in the sukkah). Therefore, if you found insects of the type “book fleas” (Liposcelis — gray-colored, about 1 mm in length), you should spray your schach with insecticide thoroughly, or wash it with extremely hot water. Then you have to shake it out well, and now you can use the schach.

However, if you found insects of the type “Lyctus” (yellowish-brown color, about 3 mm in length), then you can’t get rid of them without a professional exterminator. If you lack the time of the resources to do a professional disinfestation, you should spread a colorful or patterned sheet under the schach, in a way that will beautify your sukkah. You will have to rely on the opinion that this does not constitute a barrier between the schach and those who sit in the sukkah. You should not use a nylon tablecloth or a plain sheet for this, since this could constitute a barrier under the schach, which will render your sukkah invalid.