same here. I keep the dry chow in my crisper and and just cook up what I need. it will last a long time in cool temps and no light (the two culprits of breaking down most anything).
Good thing that you switch from the tree. In general plant bacteria cannot be transmitted from plant to other organisms, but fungi can. Also, if you let the silkies feed on it and they decimate the foliage you may lose the tree or have a year when it produces minimal foliage. Some plants actually produce chemicals the following year to ward off hungry herbivores as a defense mechanism.
Sorry, got a bit OT there 
lele
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0.1 veiled - Luna
0.2 house geckos - Gaia & Tia (both MIA 
0.2 felines - Kyndra and Líta
1.0 African Clawed Frog (for summer)
0.5 Mad. Hissers (for summer - all girls, no little ones, whew!)