In that case either very little secondary tissue is formed, as in the gourds, some Ranunculaceae, &c., or a considerable amount may be produced (clematis, barberry, ivy).
The larvae of the latter usually vacate their galls, to spin their cocoons in the earth, or, as in the case of Athalia abdominalis, Klg., of the clematis, may emerge from their shelter to feed for some days on the leaves of the gall-bearing plant.
Among indigenous fruit-bearing trees, shrubs and vines the state has the bird cherry, black cherry, blueberry, cranberry, raspberry, blackberry, gooseberry, strawberry, grape and black currant; and conspicuous among a very great variety of shrubs and flowering plants are the rose, dogwood, laurel, sumac, holly, winterberry, trilliums, anemones, arbutuses, violets, azaleas, eglantine, clematis, blue gentians, orange lilies, orchids, asters and golden rod.
In the rose, passion-flower, clematis, honeysuckle, &c., in which the flowerbuds are developed at the ends of the young shoot of the year, we have examples of plants destitute of flower-buds during the winter.
In general, each shoot makes one layer, but in plants like the Wistaria or Clematis, which make long shoots, what is called serpentine layering may be adopted; that is, the shoot is taken alternately below and above the surface, as frequently as its length permits.
Roses and clematis, however, are generally grafted from January to March and April.
- Clematis trained on Balloon-Shaped Trellis.
46 shows a pot specimen of clematis trained over a balloonshaped trellis.
Some petioles are long, slender and sensitive to contact, and function as tendrils by means of which the plant climbs; as in the l,' nasturtiums (Tropaeolum), clematis and c in others; and in compound leaves the midrib and some of the leaflets may similarly be transformed into tendrils, as in the pea and vetch.
The shrubby vegetation comprises Rosa, Rubus, Indigofera, Desmodium, Berberis, Boehmeria, Viburnum,' Clematis, with an Arundinaria.
Smilax, clematis, honeysuckle and woodbine are the commoner forest vines.