Much like the ones in the anime.
There are generally no restrictions, but I adhere most often to rational aspects whenever utilizing jutsus.
In such the case, you can focus your chakra into your hands and create a "fist-ful" of seeds, and then toss them across the battlefield if you wish.
The thing I enjoyed so much about Wood in the past was its specialty of allowing endless imagination and creativity whenever utilizing it. The simple Wooden technique is much like the D-Rank Genjutsu - the only limit is your own mind. You can create 50 pillars, even 100...mold it however you like.
I would believe that you would be able to make the seeds come out of Wooden Pillars as everything is made of your own chakra. Much like the concept of using Wooden pillars to block Sharingan users from seeing you (because they are filled with your chakra, and thus, you are interconnected with them), you can also manipulate the chakra that is directly within it when you release it. Though, of course, I believe that your chakra doesn't stay forever in the jutsu, but only when you utilize it on the spot (such as tossing out a massive wave of Wooden pillars from your arm, just like Yamato did).
As for the speculations, I leave it to you to come up with interesting strategies as I am sure you can come up with a lot of great ones.
So this next jutsu has a similar concept to the previous one.
It's a Forbidden jutsu, and can only be used once.
Again utilized through seeds the size of a grain of rice (because of this, they will hardly be noticeable and your opponents should not notice these unless they are some Doujutsu user), you can create many and spread them out throughout the battlefield, however, what is different about these is the impact it has on your opponent.
Such as, you might want to choose to aim these in certain areas, or you can simply, like the previous jutsu, let it go out through the battlefield.
Once a seed attaches onto the opponent, it looks for their chakra points, latching onto their skin as they grow roots into their body that suck their chakra. The flower grows as this happens, becoming a liability for your opponent as they are both poisoned and weakened by the flower.
If you aim this jutsu on the arm, it would disable their hands and thus, preventing them from using handseals, while on the legs, would restrict their movements. It really allows for creativity, and as time passes, the flower will only get deadlier, as the person struck by this will die in three turns.
