UNIVERSITY 



ORCHID 



teraction in such cases is to apply fire heat and ventila- 

 tion. A close, stagnant atmosphere is always to be 

 avoided. 



As a safeguard against excessive changes in humidity 

 a hygrometer should be kept in each department to as- 

 certain and regulate the degrees of moisture, especially 

 during fall and winter. When overabundant, moisture 

 can be reduced by applying fire heat and ventilation, 

 and if insufficient by wetting down the paths and 

 shelves, or pits, and reducing the ventilation. Well 

 regulated departments should be kept as near as pos- 

 sible to 70 or 75 through the day or 80 to 85 with 

 free ventilation, and about 80 at night. Just after 

 damping and watering it will often rise to 85, but this 

 is of no consequence, as it soon recedes. Orchids at 

 rest, such as Calanthes and Dendrobiums, should be 

 held at 65 to 75. In no case, where it can be avoided, 

 should it go below 60 nor rise above 90 for any length 

 of time, as serious results are very liable to follow. 



Ventilation. The ventilators should extend the en- 

 tire length on both sides of the ridge, and be supplied 

 with the best modern lifting apparatus. Extending 

 them continuously along the roof necessitates raising 

 them but a small height to afford proper circulation 

 to the plants and egress of overheated air, without los- 

 ing too much moisture. Having them on both sides 

 assists in avoiding direct drafts, by using the side pro- 

 tected from the direct wind. 



One essential point to be considered is this: When 

 should ventilation be applied so as to be of the most 

 possible benefit to the plants? Air must be given at all 

 times, when possible, to keep the atmosphere active, as 

 well as to lower temperature, also to reduce the density 

 of moisture when excessive in close, inclement weather 

 and during the night. In bright weather ventilate 

 enough to allow egress of the heated air. 



It is customary with some cultivators to close down 

 ventilators in wet weather and during the night to help 

 retain heat, etc. This is a serious mistake. It may show 

 no visible injury in bright weather, when the density of 

 moisture in the atmosphere is at a minimum, but this 

 bad practice surely accounts for the decaying of many 

 young growths, which are lost during wet, close and 

 cloudy nights. 



Prop agation. Many species of Orchids can be propa- 

 gated by division and from cuttings. This is usually 

 resorted to when it is desired to increase the stock of 

 rare and unique species and varieties. With the more 

 common species, however, it is cheaper and better to 

 buy freshly imported stock, as it often takes two, three 

 or more years to bring the young plants up to the flow- 

 ering stage. 



The pseudobulbous species, such as Cattleyas, Odon- 

 toglossums, Coslogynes, etc., are propagated by cutting 

 part way through the rhizome three or more pseudo- 

 bulbs behind the lead with a sharp knife. This will 

 usually retard the sap and force the dormant eye behind 

 the cut to grow. The back portion may then be removed 

 and potted or basketed separately, or left on the plant 

 to mature the new growth, and be removed when it 

 starts action the following season. 



With the deciduous Calanthes, the old bulbs should 

 be removed when potting them in spring and put, sev- 

 eral together, in pans or flats and partly covered with 

 sphagnum or potting compost until they start to grow, 

 when they should be potted in the regular way. Thu- 

 nias are easily propagated after the young growths are 

 well advanced, by cutting the last year's stems into 

 pieces 4 or 5 inches long and inserting the ends in 

 chopped sphagnum and sand, placing them in the propa- 

 gating house until they grow, when they may have their 

 normal heat. Dendrobiums are managed in much the 

 same way, or the old canes can be laid on wet sphag- 

 num, when many will produce new growths from the 

 side eyes on the nodes. Aerides and Vandas are in- 

 creased by removing the upper portion with a sharp 

 knife, leaving a few roots and at least a foot of stem to 

 each top. The old bases of the stems usually break new 

 growths freely, often producing several new shoots 

 from each. Cypripediums should be divided between 

 the older growths, leaving at least one old growth with 

 each lead, and potted separately, allowing them a little 

 extra moisture ^intil they start to grow. Masdevallias 



ORCHID 



1169 



and allied genera can be separated in the same manner, 

 leaving several leaves and one or more new growths or 

 leads to each piece. All species should be propagated 

 at the commencement of the growing season. 



Reproduction of Orchids from Seed. The reproduc- 

 tion of Orchids from seed through crossing and hybrid- 

 izing has been carried on for many years successfully by 

 a limited number of hybridists, principally abroad, and 

 it is only within the past 10 or 15 years that it has re- 

 ceived much attention in America, but in that limit of 

 time very many beautiful hybrids have sprung into cul- 

 tivation, and to the late firm of Pitcher & Manda, of 

 Short Hills, N. J., much credit is due for the fine work 

 they carried on in this line. Many of our establishments, 

 both private and commercial, are now paying much at- 

 tention to this branch of Orchid culture, with various 

 degrees of success. The fertilization of Orchids is very 

 easy and requires no special skill, but judgment should 

 be exercised in the selection of proper species for the 

 work, in order that the results may be an improvement 

 over both parents, if possible. 



The seed-bearing parent should possess a good, vig- 

 orous constitution, of free-growing and flowering habit, 

 as the hybrids usually follow this parent in form of 

 growth, and the pollen parent in color of flower. Fer- 

 tilization is effected by placing one or more of the pol- 

 linia or pollen masses on the stigma of the flower to be 

 fertilized, selecting always plants of relatively the same 

 genus for the operation. Crosses between genera widely 

 removed from each other in general character usually 

 prove fruitless, for though the ovary may become stimu- 

 lated by foreign pollinia and an apparently successful 

 cross be effected, the seeds will either fail to mature or 

 the results will follow the seed parent in every detail. 

 It takes about a year to ripen the seed of most Or- 

 chids in our climate, with exceptions in a few genera. 

 Masdevallias mature in about six months and Selenipe- 

 diums in about three months. 



The seeds germinate best when sown soon after ma- 

 turity, and many lose their vitality in a few months if 

 kept too dry and warm. When sowing the seeds the 

 best results are often obtained when they are dusted 

 on the surface of pots or baskets containing a plant of 

 the same genus as the seed and carefully watered with 

 a very fine rose until they become attached, watching 

 carefully for snails, slugs, and depredators in general 

 that infest the compost. The pots or baskets selected 

 should have a favorable-looking surface, with the com- 

 post in good condition, firm and free from fungi. Use 

 pots or baskets that will not have to be disturbed for a 

 year or more, as it often takes that length of time for 

 the seedlings to come through. Seed sown in early 

 spring seems to germinate soonest. The writer has had 

 Selenipedium seedlings up in three months from sow- 

 ing, and again has waited for Cypripedium twenty-three 

 months before the seedlings appeared. 



After the seedlings have perfected 2 or 3 leaves it is 

 quite safe to remove them to small pots, singly, or ser- 

 eral to a small pan, using compost 

 of the same material as that for the 

 parent, but cut a trifle finer. 



Many tiny seedlings are lost short- 

 ly after germinating, through the 

 soil becoming sour or through fungi. 

 When thus at- 

 tacked they 

 should be trans- 

 ferred to other 

 pots or baskets 

 not infested. 



Fig. 1584 illus 

 trates a newly 

 germinated seed- 

 ling of P h a i u s 

 hybridus: Fig. 1585 a three-months - old seedling of 

 Cypripedium insigne, var. Sanderce, in proper con- 

 dition to be transferred to a pot ; Fig. 1586, eight- 

 months-old plant of Phaius Wallichii ; Fig. 1587 a 

 twelve-months-old hybrid Cattleya ( C. intermedia x C. 

 labiata); Fig. 1588 a Cypripedium thirteen months old; 

 Fig. 1589 a two-year-old hybrid between a Cattleya and 

 Lselia ((7. intermedia x L. prcestans). 

 The raising of Orchids from seed should be encour- 



1584. 

 Newly germinated 



seedling. 

 (Phaius hybridus.) 



1585. Three months 

 from seed, and 

 ready to transfer 

 to a pot. ( Cypri- 

 pedium insigne, 

 var. Sanderce.) 



