Curious Crop Exchange: Why no BTN materials?

Anybody else think its strange that there's almost no botany-related materials available but loads of mining-related materials? I've been making a lot of furniture lately and stuff like spruce lumber is always on a massive shortage. It seems odd that I can go use voidrakes to get more darksteel than I can even use yet not be able to get spruce logs, the BTN equivalent.

EDIT: And yes, I've already got two retainers on spruce logs. They really don't bring back much at all. It still seems odd that BTN gets left out of something botany related.

I'm going to hazard a guess that Darksteel's inclusion over Spruce is due to its usage in airships (you need...so much...)

In sort of a way it makes sense. Gardening is more or less locked to housing, as are airships. In fact, almost all the of materials available for the curious crop exchange are materials I needed a lot of for airships, or materials used in housing items, such as Rush Grass and Floss Silk. Now I know you need some Spruce and other botany materials for airships, but not near the same level of magnitude as Darksteel.

If you need a lot of Spruce, you probably want to go get some yourself in addition to using your Retainers. With a high level trait, you get access to everything at the node (given the node’s level) so all your GP can be devoted towards increasing the yield, and you get all six swings to take the logs. At 500 GP you can increase the take from 18 to 30 logs per visit, and at 100 GP per swing Bountiful Yield 2 can add 3 on top of that, for two or three swings (depending upon your total GP, I only get two as I don’t bother with GP food). 36 Logs per visit is quite a lot, basically 12 lumber or 6 treated lumber.

While that may not be enough for whatever is being crafted, that does dramatically reduce the number of trips Retainers need to be sent on. In fact, I’d say that it relegates Retainers to being a supplemental rather than primary source for the starred materials.