Not sure if it's too late not, but if it's not, DON'T. I understand that the price is attractive compared to TreePro, Plantra, or Tubex. My experience with these has been very poor. It's wasted money and not worth your valuable time. I used over a thousand of these to complete a reforestation contract I had with the NRCS. I chose them because we had unexpected medical bills the final year of my contract, and I needed to go with the cheapest option. They have multiple issues:
1) It's nearly impossible to control weeds around the trees unless you're going to use a metal blade weed wacker around them every two weeks.
2) The holes are way too large. The trees turn into shrubs. If the central leader pokes out of the large holes, deer walk by and nip the central leader. Then a secondary bud has to become the new central leader. Hopefully it never pokes out. When it does (inevitably) a tertiary bud becomes the central leader. The result is 12" - 18" oak bushes.
3) These are quite fragile and will get torn as soon as a branch, deer, squirrel, or whatever hooks onto them.
4) They are not really "rigid", at least not in the long term. When you install them in the spring, they'll seem rigid. But they soften up and fold over in the summer heat.
For what it's worth, I also used hardwood stakes with mine (true 3/4" x 2"). Huge mistake. All of my stakes rotted. Use plastic PVC pipe. I bought 10' lengths for $1.19/ea and cut them in half. I was able to cut 100 10' lengths to make 200 stakes in about 15 minutes. I just laid them out on saw horses. It was easier than I thought it would be. For nearly the same cost as the cheapest bamboo or hardwood stakes, you have weather proof, durable, reusable stakes.