206 AMERICAN HONEY PLANTS 



plants as follows Andromeda japonica, A. polifolia, A. Catesbaei, A. 

 calyculata, Kalmia latifolia, Monotropa uniflora, Pieris formosa, P. 

 ovalifolia, Rhododendron grande, R. barbatum, and R. fulgens. It has 



been recorded for additional plants by Greshoff, who mentions the fol- 

 lowing plants which produce poisonous honey: Nerium Oleander, Cy- 

 tisus Laburnum, Pieris ovalifolia, Callotropis procera. Daphne, Pontica, 

 Buxus balearica, Clerodendron serratum, C. Bhramaramari, Sapindus 

 emarginatus. (It is said that thousands of bees are killed by this 

 honey.) Centaurea scabiosa, Carduus natans, Scabiosa succisa, A 

 South African species of Euphorbia also produces a poisonous honey 

 which was not noted by Greshofif. 



POISONWOOD (Metopium metopium). 



The poisonwood is a tree found in southern Florida, the West Indies 

 and Central America. It is known by a variety of names, bum-wood, hog- 

 gum, coral sumac or doctor-gum. Its sap is dangerously poisonous, and 

 some persons are affected by a near approach to the tree. The tree reaches 

 a height of more than forty feet and in south Florida it is the source of 

 large quantities of surplus honey of good quality. The honey is usually 

 blended with that of other sources blooming during the same period. 



The tree has a thin bark which splits into large scales as it grows older, 

 These are of a reddish brown color, brighter on the inside. It is sometimes 

 confused with manchineel and is often classified as a Rhus. 



POLLEN. 



Pollen represents the male element of reproduction in seed plants. 

 The flowering plants are normally reproduced by seed. Fertilization is 

 brought about by the intervention of the grains of pollen which are borne 

 by the stamens or male organs. In the corn plant the stamens are pro- 

 duced in the tassels where pollen is developed in great abundance. The 

 pistils, or female organs, are represented by the silks attached to the ear. 

 There is a separate silk attached to each kernel, and each must be sep- 

 arately fertilized. In many plants both stamens and pistils occur in the 

 same blossom, as is the case with apples, pears, etc. In some cases the 

 stamens or male organs are borne on a separate plant or tree, as is the 

 case with the persimmon. Cucumbers have the separate organs in separate 

 flowers. In order to insure fertilization it is necessary that the pollen 

 grains be carried from the stamens to the pistils. In the grasses and sim- 

 ilar plants this is usually acomplished by the wind, while in most fruits, 

 insects are the principal agents. 



Pollen grains are very minute and are produced in small sacs in the 

 tip of the stamen, commonly called anther. When ripe, the breaking of the 

 sac sets the grains free in great abundance. A single grain is sufficient 

 to fertilize an ovule and produce a seed; yet, because of the distance be- 

 tween the stamens and pistils, large quantities of the pollen or flower dust 

 are necessary to insure pollination. Ragweed and corn produce pollen in 

 such abundance that one brushing by the plants is dusted so freely as to 

 appear to be covered with flour. 



Pollen is of special importance to the beekeeper, since it serves as food 

 for young bees. It is the sole source of nitrogenous food for the growing 



