The Japanese maple tree (acer palmatum) is a term given to actually hundreds of varieties of trees. Generally, they are a smaller tree with distinct foliage--dissected leaves in colors ranging from dark green to bright red in the fall. The tree has a way of slowly growing with a mounding effect that makes it attractive as a landscape plant. Propagation is by seeds, grafting and softwood cuttings with seeds being the simplest and least expensive way to plant.
Collect the seeds in the summer when they start to flutter to the ground. Start with several seeds since you don't know how many will actually germinate. Break off the wings being careful not to damage the seed.
Stratify the seeds in a dry envelope or small paper bag in a warm but dark area until September for their warm stratification time. After that, place them in a plastic bag filled with moist sphagnum moss, close and place in a refrigerator for 120 days, for their cold stratification.
Plant the seeds about 1 inch deep in a potting soil mix made of three parts ground composted pine bark and one part perlite. This will keep the soil on the acidic side of the pH scale. Place them in a warm and sunny spot until the weather has warmed up outside to be above freezing.
Water the seeds regularly until they sprout, making sure the soil stays moist. Once they start developing leaves, you can water less allowing the top of the soil to dry before watering.
Transplant the seedlings outside to a permanent spot either in a large container or on a mound of soil where they can get full sun and are sheltered from strong winds. They will grow slowly but will still look good even as a small tree.