I have a Thuja that started growing these brown things at the end of the leaves. At first I thought the plant was undernourished but I realized they might be seeds. I took a bunch of them and set them aside thinking I might try to plant them. Now some of the brown bits at the end of the plant which I have not removed seem to have grown in to spiky green bits. I don't know if these are new limbs, parts or seeds. I did some searches and found pics but no additional information.

This is a link of what it looks like http://www.weberseeds.de/gallery/chinese-arborvitae.jpgow: