Trees, Flowers and other Plants
These representations of natural objects are very commonly found in mediaeval Heraldry and there are quite a few available.
bunch of grapes, reed, bundle of reeds, thistle, vine, vine leaf, oak leaf, acorn
The Farming and Tools category also include a Corn sheaf
Apple, fir, oak and a generic tree
Cinquefoil, octofoil, quatrefoil, rose, trefoil, sexfoil, cornflower, poppy, daisy, tulip, bunch of tulips, lily
Common features (that can be given a different colour) include slipped, leaved, trunked