Here in coastal Calif. (and Oakland area 200 miles north) they do well in partial shade. I have been told the lacier the leaf is, the definate need for shade.

I have three in partial shade and all do well.

You might want to post on Maples forum or Japanese gardens forum for suggestions of JMs for shady conditions. Quit alot of discussion of JMs there. I'm no expert but I do know there are soooo many cultivars that need shady areas, I can't list them all. They also very so greatly in size, texture, color and form. Google "Japanese Maples for shade" you will find tons of informatio also.
Cheers

You might want to post on Maples forum or Japanese gardens forum for suggestions of JMs for shady conditions. Quit alot of discussion of JMs there. I'm no expert but I do know there are soooo many cultivars that need shady areas, I can't list them all. They also very so greatly in size, texture, color and form. Google "Japanese Maples for shade" you will find tons of informatio also.
Cheers

Good advice above :-) But as a Maples forum regular, let me say this - the warmer the climate, the more shade a JM can tolerate. Red leaved varieties may lose color ("green out") in much shade but the very light colored leaves (gold, chartreuse, yellow-green) and those with very narrow, linearlobum-type foliage do best in at least some shade. And any variegated forms must have protection from afternoon sun at the very least.

The only other concern with planting close to the pines is maintaining adequate soil moisture. Larger growing conifers tend to suck moisture out of the soil and JM's are not happy in dry conditions. You may need to attend to water needs in this location.

btw irisgal, red laceleaf maples are particularly sun tolerant, even in Sacramento!

Thanks for your replies, everyone!