Monarch butterflies have magnitite (a mineral) inside their heads and this helps them determine 'North', just like a magnet.
Canadian Tree Guide
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Basswood
basswoodTilia americana L.
Basswood is a medium-sized (>27 m) tree. Leaves have asymmetrical bases. Small creamy yellow flowers are pungent and honeybees produce a fine honey from the nectar. The fruits usually contain one seed, but sometimes there are a few in a cluster, affixed to one wing. The First Peoples used the bark for weaving ropes.
Tree Guide
