D H Lawrence preferred nature to people. In the passage below, it seems to me, he describes sex–only with vegetation rather than another human. I think he writes this partly because of his preference for vegetation over people but also because he couldn’t in “Women in Love” published in 1920 write about sex between humans. He did in “Lady Chatterley’s Lover” published in 1928, and we all know there that led. https://richardswsmith.wordpress.com/2014/10/04/lady-chatterleys-lover-was-in-both-catholic-and-puritanical-traditions/
The context of this extraordinary passage is that Rupert Birkin (surely modelled on Lawrence himself) has been hit over the head with a lapis lazuli ball (very Lawrentian that, he loves colour) by his ex-lover Hermione Roddice (modelled to her dislike on Ottoline Morell https://richardswsmith.wordpress.com/2018/03/04/ottoline-morrell-as-hermione-roddice-in-women-in-love/ ). For many this passage will seem ridiculous, like a pastiche, but it worked for me.
Birkin, barely conscious, and yet perfectly direct in his motion, went out of the house and straight across the park, to the open country, to the hills. The brilliant day had become overcast, spots of rain were falling. He wandered on to a wild valley-side, where were thickets of hazel, many flowers, tufts of heather, and little clumps of young fir trees, budding with soft paws. It was rather wet everywhere, there was a stream running down at the bottom of the valley, which was gloomy, or seemed gloomy. He was aware that he could not regain his consciousness, that he was moving in a sort of darkness.
Yet he wanted something. He was happy in the wet hillside that was overgrown and obscure with bushes and flowers. He wanted to touch them all, to saturate himself with the touch of them all. He took off his clothes, and sat down naked among the primroses, moving his feet softly among the primroses, his legs, his knees, his arms right up to the arm-pits, lying down and letting them touch his belly, his breasts. It was such a fine, cool, subtle touch all over him, he seemed to saturate himself with their contact.
But they were too soft. He went through the long grass to a clump of young fir-trees that were no higher than a man. The soft sharp boughs beat upon him, as he moved in keen pangs against them, threw little cold showers of drops on his belly, and beat his loins with their clusters of soft-sharp needles. There was a thistle which pricked him vividly, but not too much, because all his movements were too discriminate and soft. To lie down and roll in the sticky, cool young hyacinths, to lie on one’s belly and cover one’s back with handfuls of fine wet grass, soft as a breath, soft and more delicate and more beautiful than the touch of any woman; and then to sting one’s thigh against the living dark bristles of the fir-boughs; and then to feel the light whip of the hazel on one’s shoulders, stinging, and then to clasp the silvery birch-trunk against one’s breast, its smoothness, its hardness, its vital knots and ridges—this was good, this was all very good, very satisfying. Nothing else would do, nothing else would satisfy, except this coolness and subtlety of vegetation travelling into one’s blood. How fortunate he was, that there was this lovely, subtle, responsive vegetation, waiting for him, as he waited for it; how fulfilled he was, how happy!