When something is stalkless, it means it doesn't have a stalk, like a flower without a stem.
Stalkless things are usually small and might be easier to handle.
Examples:
The flower is stalkless, so it's just a little bunch of petals.
I found a stalkless apple in the orchard.
She picked the stalkless berry and ate it.
The stalkless pumpkin rolled away.
The stalkless tree looked very strange in the forest.
The stalkless mushroom was very small and cute.