Boletus Zelleri -

This is the giveaway! The stem is usually yellow but heavily "flushed" or streaked with bright red or reddish-brown.

If you bruise the yellow pores or cut the flesh, you might see a faint, slow shift toward a blue color—a common trait in many boletes. Where and When to Find Them boletus zelleri

They are mycorrhizal with conifers, meaning they have a symbiotic relationship with tree roots. You’ll frequently find them under Douglas firs or in mixed coastal forests. This is the giveaway