just the style is old
I'm an old guy lol I always like the old style paintings. But I do really like Ice Formation, its probably my favorite. Piney - 1976 and Snowy Trees - 1975 are interesting because I see this kind of painting or photography alot with birch trees with their white bark.
Like this photo I quickly pulled off the internet.
Looks like those paintings are the winner today as others mentioned them too.
Wow, these trees are so beautiful. I'd love to be able to photograph such forest once.