490 FUNDAMENTALS OF FRUIT PRODUCTION 



cultivation, limit its usefulness and range. The more important of 

 these characteristics, as they concern the fruit grower, are mentioned 

 here. 



Imperfect Flowers: Dicecious and MoncEcious Plants. — Most 

 fruit-producing species bear perfect flowers. There are some, however, 

 in which the sexes are separated. In certain species, such as the walnut 

 and pecan, they are found in different flowers on the same tree or plant; 

 in others, such as the papaya and sometimes the strawberry, they are 

 found on different plants. 



Monoecious plants bear the pistillate and staminate flowers on the 

 same individual and are always fruitful — at least theoretically — and rather 

 frequently they are self fruitful. Certainly the segregation of the sexes 

 to separate flowers of the plant does not in itself interfere with pollination, 

 fruit setting and fruitfulness. Among the more common fruits that are 

 monoecious are the walnut, pecan, filbert and chestnut. The members of 

 the Cucurbitacese also are for most part monoecious. 



Probably the strawberry is the most widely grown of the dioecious 

 fruits. A comparatively large percentage of its varieties bear perfect 

 flowers, but some of the best are pistillate. For many years after 

 the strawberry was introduced into cultivation no attention was paid to 

 the matter of planting so as to secure pollination of the pistillate varieties, 

 hence much of the failure of the fruit to set properly in the plantations of 

 a century ago. It was not until the observations of Nicholas Longworth 

 of Cincinnati were brought to the attention of horticulturists generally 

 in the fifties that the unisexuality shown by plants of this species attained 

 recognition and planting practices were modified accordingly. Experi- 

 ence has taught long since that these pistillate sorts should be interplanted 

 with perfect flowering varieties. There are many strawberry varieties 

 classified as perfect flowering that produce only small amounts of pollen. 

 These, as well as the imperfect sorts, should be interplanted with good 

 pollen producers. 



The Japanese persimmon or kaki presents a very interesting case of 

 sex distribution. Many of its varieties, such as Tanenashi, Hyakume, 

 Hachiya and Costata, produce only pistillate flowers year after year. 

 These are called "pistiUate constants" by Hume.^" Certain other varie- 

 ties bear each year pistillate flowers and also some staminate flowers; 

 these he designates as "staminate constants." Still other varieties bear 

 only pistillate flowers some seasons and in other seasons both pistillate 

 and staminate. These are called "staminate sporadics." Hume'^^ also 

 records the occasional appearance of perfect flowers on trees that regularly 

 or occasionally bear staminate flowers, though they have not been 

 found on plants of the pistillate constant type. In other words, certain 

 varieties are monoecious, others dioecious; still others vary from the one' 

 condition to the other and occasionally a variety becomes temporarily 



