I don't know if this is a copy pasta but it's awesome. Let me just post this and I'll edit with the link https://sh.itjust.works/comment/21244535

"I want to pollinate you and cover you in pine cones," he whispered and she felt her sap run hot with desire. She shivered from more than the cool spring wind on her bark. His needles moved against hers in the breeze, tickling and prickling her deliciously and she could tell his wood was knotted and hard as his sticky sap dripped from it. She craved to feel him against her, branches and bark and overwhelming passion. And then she felt it, the microspores of his grainy discharge, carrying his potent gametophytes, exploded into her, settling among her needles. Her bark tingled with exquisite, syngamic release as her branches quivered in the cool spring wind and deep inside her ovules she felt his gametes fuse with hers. "Yes," she whispered in the wind. "Take me! Fertilize me! Give me your nuts!"

"You know I'm your half brother," he whispered as she shuddered in climax. "I don't care," she whispered back. "That makes it hotter."