It is a shame that the Chief Rabbis have to bother themselves with putting out such statements, but, alas, such is the situation and state of affairs..

The Chief Rabbis of Israel put out a joint statement saying it is prohibited for people to steal and cut down sechach and aravos from trees that grow by the riverside around Israel. These are generally protected, and cutting the branches off is illegal, is theft, and damages the trees.

Also, one should refrain from buying aravos and sechach from merchants whom you suspect are selling merchandise from less than reputable sources...