I have a large Flowering Plum in our front yard I want to graft fruit into. 
I went to a local orchard and he gave me lots of clippings from a variety of stone fruit trees.
I have them stored outside right now, but I want to put some in the refrigerator to keep until spring.
One thing I have heard is to only use first year but that will be too small to whip graft with.
Is it OK to use 2nd year or older wood as scionwood?
Dax (@ barkslip) said that he’ll use 2nd year wood. I did it once on pear and it worked OK. I’d certainly do it if I had to.
If you go with second year wood, just make sure you have live buds or at least a couple buds of this years wood. I often use the double tongue side graft in situations where you want to graft a smaller scion onto an older branch, then once the scion is actively growing I prune off the larger branch just above the graft union. Either way should work.
Good luck
Dennis
Kent, wa
When I have small wood like your 1-year wood I just do bark or cleft grafts. The 1-year wood will be more likely to take since it is younger. That said I have used 2-year wood when that is all I had and it worked OK.
I just looked this graft up and it looks a lot like a Whip-and-Tongue Graft but to the side of a larger branch.
You are very right! Which is why it is one of the best tools in your grafting toolkit! Whichever method gives you the best match of cambium layers is the method you should use. It took me several years of failures to discover it, but it’s one of the most successful techniques you can use
Mark,
I spent several weeks doing my third review of Hartmann and Kesterson Plant Propagation Guide. I outlined all the factors one must do correctly to obtain a successful graft. If you would like my notes I would be happy to send it to you. If you have access to a library to obtain this text, it’s worth reading.
Dennis
@DennisD I am an Engineer as well (but not retired yet). I am looking forward to trying grafting. I found a local retired IT guy that has a orchard nearby that has been a great help. I gave me a boatload of Peach, Cherry, and Nectarine trimmings to try.
Sure @DennisD, that would be great. I love to learn (and teach) - I leach Engineering evenings at a local University.
Fantastic Mark, I am a retired civil, so good to meet you. I will send you my notes.
Mark,
This may be helpful, just received from Marta in Ca,
Adara compatibility paper Adara, A Plum Rootstock for Cherries and Other Stone Fruit Species in: HortScience Volume 30 Issue 6 (1995)
Thanks @DennisD. I have run into some lore/confusion on what you can graft into a plum. A local expert told me that you could only graft plums into plums. I suspect she did not have a lot of examples and the ones she had heard of did not work, but there can be a lot of reasons for a graft to fail. It is great to see a broad study like this.
Also should you determine you need an interstem, you can get Adara scions from Marta at
2h
Puente is the trademarked name for Adara. I have Adara scions at reallygoodplants.com
I toped my > 20 years old flowering plum and grafted the shoots with apricots and plums. Apricots (and plums) are doing well so far, but I don’t know about the long term compatibility. The flowering plums may also be different, and yours
can behave differently.I believe my tree is a Purple Leaf Plum (Prunus cerasifera) and it looks like @speedster1, @SteveM and @Matt_in_Maryland have all tried grafting fruit into one before
@Barkslip, what are your reasons for opting to discard the tip nodes for grafting?
(Other than sometimes bloom buds, I’ve had no problems using tip ends.)
If I can physically bend the wood where it will cave in, that’s not good budwood… and naturally-speaking the reason being the buds below that less mature wood will yield more success (long-term). It will have something to do with the Genus/species and/or cultivar from time to time, too. You learn what type of wood certain-trees, produce. That’ll save you time every year (if you honestly can remember!) 
