In our propagation beds we have noticed on the underside of the poinsettia leaf that there are growths just on the veins of the leaf. The are gray black and purple in color. Does anybody have a clue what this is???

Curious, can you send some images?

We really aren't sure what you are descibing so a picture would be really helpful here. You can post images by creating a photo album in the same place you created a new topic. If you have trouble posting images you can also email them to rsiemonsma@eckeranch.com. Thanks!