River birches propagate reliably from fresh seeds, which will germinate rapidly if pretreated and sown under warm conditions. However, the seeds are extremely sensitive to drying out and must continually be kept moist after sowing to ensure a successful outcome.

To stratify indoors, mix the seed with a moistened, sterile, peat based growing medium in a container, wrap in a ventilated bag, and place it in a refrigerator for 12 to 20 weeks. In the spring plant the seed in a sheltered spot outside to grow into seedlings. Transplant to permanent site when well rooted.

River Birch produces seed pods that are unique to the variety. The seed pods are long and narrow and look like a skinny caterpillar. The pods of the tree are brown. The seeds are stacked on top of one another so when you break them; they fall apart.

Seeds are collected by hand from standing trees or from felled trees. The shattering habit of the birch catkins make it advisable that collectors place the catkins into picking bags as picked instead of allowing them to fall on to tarps.. . . . .364011234533!]0000000000000009783314145466!]