It's a paw climate! The warmth has arrived in the Pacific Northwest on this pre-fall day. Paw organic products need heat like this to age.
A lot of pawpaw fruitlets appeared to pine for more sweltering days back toward the beginning of July.
The elongated, green paw organic products are developing at Raintree. I was simply keeping an eye on them... As orchard manager, quite a bit of my work at Raintree happens in our plantations. I additionally have the chance to work in our nurseries, gaining from our horticulturist.
One of the tasks I've assisted within the nurseries is grafting pawpaws. I am a decent novice grafter, having just started to learn since beginning at Raintree once again eighteen months back. This post will depict my learning procedure and offer some of what I know; however, obviously, I'm no master yet! I'll concentrate on my paw joining experience here, but I would like to continue to learn more about grafting in general.
The thought behind grafting is basically to combine two plant stocks. Scionwood from a chose assortment (chosen for all kinds of reasons, but commonly its fruit) is put onto a chose rootstock. A rootstock may be chosen for its vigor, disease resistance, adaptation to a certain environment, or different reasons.
Vegetative buds on the scion wood should be recognized from flower (aka fruit) buds in pawpaws because their buds develop deterministically in that manner. A vegetative bud will grow into a leaf or a stem, whereas a flower bud can only become a flower and then fruit. Paw-paw (the main species being Asimina triloba) are tropical-seeming plants in part because they bear fruit directly on the stem. To humor the botanist in me or the reader, I'll throw out the term cauliflory. Indeed, pawpaws are tropical. They're the northernmost member of the custard apple or soursop family (Annonaceae) and the only one that has escaped the tropics. Pawpaws' champion fruit ranks as the largest edible fruit in temperate North America. The broad-leaved, shrubby, clonally spreading paw ranges in the East all the way up to Ontario, Canada. Although the fruit's perishable nature has precluded its appearance in grocery bins, local economies exist around paw patches. Pawpaws have made something of a cultural impression if only regional: <https://www.youtube.com/watch?v=SidjBL6tQF4> (the song "Paw Paw Patch" by Pete Seeger, Mika Seeger, and Rev. Larry Eisenberg from Smithsonian Folkways Recordings on YouTube)
Paw blossoms show up before the leaves in the spring and are borne directly on the stems.
Anyway, I could go on about paw natural history for a while, but let's circle back to that some other time. For now, onward with the grafting...
We use whip-and-tongue grafting to fuse together paw rootstock and scion wood grown in our orchards. I match girths (or calipers) of rootstock and scion as the first key step in the process. The rootstock and scion should be as close to the same thickness as possible. Then, I cut upward at a steep angle on the rootstock. I make sure to have the flat side of the grafting knife towards the base of the rootstock and the beveled side away, ensuring a clean surface for fusing to the scion wood. Then, I do the reverse to the scion stick, cutting downward at a steep angle away from the top. Again, the flat side of the knife makes a clean cut on the side of the scion to join with the rootstock. Cutting inward into both scion and rootstock allows cross-hatching them for strength. The pieces slide into each other. The main point is to have the cambium layer (actively growing tissue that generates xylem and phloem) of both lines up as much as possible. For this to work, the cambia have to fuse together. Tape, band, parafilm, or the like gets wrapped around the join (the graft union) to help hold the two pieces together and prevent drying out. A dab of wood glue to the top of the freshly cut scion wood (cut back so that only one or two vegetative buds are left above the graft union) helps ward off desiccation as well.
Grafting is both art and science, I think. I'm eager to keep practicing to improve my art. I have worked some with whip-and-tongue on other species. I'd like to learn other styles of grafting, too. It's amazing that two (or more!) individual plants can be joined together with such simple technology, as people have done since Roman times!
Happy growing! Because, after all, change is the only constant.
Over all look so beautiful! Your tree nursery is really, really pretty! Thanks for taking us on a tour of where your tree sits, and for sharing information about your whole trees. I will have to pay more attention towards tree nursery.
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