What can I do if I have no saplings?

Solution 1:

That depends on how far you are in the game. As usual in modded Minecraft, there are many ways to get something.

When you hover over a sapling in the Not Enough Items (or however that variation of the mod is called) item list and press R (or another key, if you changed the keybind), you should see all possible ways to get that item.

In the case of saplings I'm pretty sure that I've seen it in a lootbag before, so you could build a mob farm. As long as you have some opaque blocks, that should be possible.

But in general it's always a good idea to leave a few saplings save in a chests that you never use, just in case. It's like the skyblock equivalent of "never dig straight down".

Solution 2:

If you have a sieve you could sift dirt. However, this is a tough challenge due to the low drop rate.

Sieved items