There are several ways to propagate pecan trees. Starting them from seed is the least expensive and easiest method. It's best to stratify the seeds over the winter and plant them in the spring, according to agriculturists at Oklahoma State University. The pecan trees will grow slowly during the first two to three years as they are producing a long tap root, so don't be alarmed if your tree appears to have stopped growing. Collect pecans as soon as they fall from the tree for best results.
Place the pecans in a bowl of room-temperature water and allow them to soak for 24 hours.
Pour moist sand into the plastic bag until it reaches 3 inches from the bottom. Push the pecans into the sand, seal the bag and place it in the refrigerator for 120 days. Check the sand periodically to ensure that it remains moist.
Prepare the seedbed by tilling the soil to a depth of 12 inches. Add a 3-inch layer of compost to the soil and mix it to a depth of 8 inches.
Remove the pecans from the bag in early spring. Plant them, 2 inches deep. Agriculturists with the University of Missouri suggest planting 3 to 5 seeds in each location in which you would like a tree to grow. Mark the area so that you will remember where each group of pecans is planted.
Select, during the first year, which of the trees from each group you will keep. It should be the strongest and straightest. Dig some of the soil away from the weaker trees to locate the root collar (the area in which the top of the rootball joins the stem), and cut them off just slightly below that area.