What is the effect to the survival of plants if there are no humans and animals?

Question

Humans and animals somehow depends on plants to survive. Can plants survive even without humans and animals?

Answer 1

One of the most immediate effects would be due to lack of pollination. Most flowering plants (angiosperms) have evolved to depend on animals (insects, birds, small mammals, etc.) for pollination. No pollination =no seeds= no offspring=extinction. The plant population would rapidly shift towards wind- pollinated plants (like the grasses), gymnosperms (like pines) and the non-flowering plants including mosses and ferns.

Answer 2

Not in the long term.
Oxygen is toxic waste to plants just as CO2 is to animals.
Too much and they die.

Long before that the danger from fire increases as the O2 level rises.

Also animals cycle nitrogen back into the soil faster than plants alone.