Antiseptic containers should be provided after sterilization is completed. Test tubes are satisfactory in a number of respects. Medium is placed in the tubes and the tubes laid on their side to provide more planting surface. The advantages of the small tubes are that part of the seed may be saved for separate planting in case contamination spoils one planting and, since the tubes are on their sides while planting takes place, that there is less oppor­tunity for fungus spores to fall into them. A major disadvantage is that a small tube may not hold enough medium to nourish the seed over a protracted period. Erlenmeyer flasks, also widely used, provide generous planting surfaces. Whatever the container, it should have been sterilized in a pressure cooker or autoclave for thirty minutes at fifteen pounds pressure. Oven sterilization over a period of three successive days will kill dormant spores if the pressure method is not practicable.

There is wide variation in the kinds of planting enclosures used, the choice often being determined by practical considerations. Some growers find a case with a glass front both satisfactory and economical. Such a case, with armholes at the sides so that work can be done under aseptic conditions, prevents contamination from air or breath and yet gives good visibility. Such elaborate precautions may be obviated by the sterilizing procedure sug­gested by McAlpine. It is still advisable, however, to spray lightly if an ordinary room is used. Fungi spores travel on dust particles floating in the air, and spraying causes them to fall to the floor.

New methods of air-conditioning and electronic dust removal will simplify this problem in the future.

The planting medium must next be provided. A wide choice of media is available. Orchid magazines carry names of firms that sell the necessary chemicals as well as prepared products. Some of the media available, such as Difco Bacto Orchid Agar, require only the addition of water. Many growers, however, prefer to make their own mixtures. Among formulas that can be used the following are reliable and highly satisfactory:

Knudson's Solution 'B'
Calcium nitrate, Ca(NOs)24H2O 1  gm.
Monobasic potassium phosphate, K2HPO4 0.25     gm.
Magnesium sulfate, MgS04 + 7H2O 0.25       gm.
Ammonium sulfate, (XH4)2SO4 0.50 gm.
Ferric phosphate, FePO4 + 411*0    .0.025 gm.
Sucrose (cane sugar)  20  gm.
Agar  15  gm.
Distilled water  1  liter
Add 0.1 normal hydrochloric acid (HC1)—enough to bring solution to a pH of 4.8-5.2.
Knudson's Solution 'C
Calcium nitrate, Ca.(NO3)24H2O 1  gm.
Monobasic potassium phosphate, K2HPO4 0.25     gm.
Magnesium sulfate, MgSO4 + 7H2O 0.25     gm.
Ammonium sulfate, (NH4)oSO4 0.50     gm.
Ferrous sulfate, FeSO4 + 7H2O 0.025   gm.
Manganese sulfate, MnS04 + 4H2O 0.0075 gm.
Sucrose 20  gm.
Agar   12-15 gm.
Distilled water  1 liter
Add 0.1 normal hydrochloric acid (HCI)—enough to bring the pH up to 4.8 to 5.2.

The agar should be cut into strips (it may come that way) and dissolved in a small amount of water in a double boiler. It should be watched and stirred to avoid burning. The nutrients should be dissolved in a small amount of distilled water and then added to the remainder of the water. While this mixture is kept just below the boiling point, the agar and sugar should be added. The whole should be mixed thoroughly, tested for pH, and poured into the waiting flasks or tubes. Use of a funnel will prevent the mixture from adhering to the mouth and sides of the receptacle. The flasks or tubes are then sterilized in the autoclave, pressure cooker, or oven. It is wise to test the pH again after sterilizing. If the medium is then too acid, a few drops of o.i normal sodium hydroxide will provide proper compensation. Tests for acidity may be made with indicator strips of nitrazene papers, a potentiometer, or a La Motte Block Comparator.

The materials are now ready for the final operation of 'planting.' A platinum needle or loop, which may be readily sterilized in flame, is ideal, but a long-handled spoon, a pipette, or an eye-dropper are all satisfactory. Sterilized seed is floated in a vial con­taining a bit of distilled water. The seeds (so tiny that they have the appearance of powder) are taken up with the tool and scat­tered over the planting surface in the flask or tube. A rolled stopper of cotton (flamed to kill fungus) should have been kept in the mouth of the flask, being removed only long enough to permit the seed to be placed inside. It may be necessary to rotate the flask rapidly to spread the seed evenly in the medium. Seed should not be allowed to fall on the sides of the flask, and crowding should be avoided.

After the seed has been introduced, the cotton stopper should again be flamed over a Bunsen burner and the mouth of the flask and the stopper wrapped lightly with paper. The flasks should be kept at an even temperature of not lower than 650 F. nor higher than 8o° F. A temperature of somewhat above the 65 ° minimum is most desirable. The flasks should be kept by themselves in some kind of an enclosure (a Wardian case in the greenhouse is excellent) where they may be protected from sun and excessive moisture and moved as little as possible. This stage of culture will last from eight months to over a year.

When incipient roots up to a quarter of an inch long appear, the seedlings are ready for repotting. Polypodium seems a very congenial medium. A mixture of shredded Polypodium and vermiculite is ideal. This is patted damply and firmly (although extremes in both are to be avoided) into two- or three-inch pots. The tiny plants can be shaken onto a clean Turkish towel or into a saucer of clean water, separated gently from remaining agar, dried slightly, and placed in some regular order in the pots. Small holes may be prepared in the medium by using a small, sharpened stick or tweezers. The root end is placed in the hole and the medium gently pressed around it. Each pot will accommodate from twenty to twenty-five baby orchids. As the seedlings do best in the company of others, we have the 'community pot.'

These pots may be put in a shaded part of the warm greenhouse, although some cautious growers prefer to seclude them in a Wardian case. Community pots in the greenhouse may be covered lightly with a pane of glass, but simple protection from the sun appears to be sufficient. They must not become chilled or too wet, for they will damp off. It is disastrous, however, to allow them to dry out, as dried-out seedlings will disappear over­night. As the seedlings are delicate, naturally all precautions against snails, slugs, thrips, and aphis must be taken.

From this point on, success with the seedlings lies in keeping them moving right along. They should be repotted at least every eight months. The second potting may take them directly to an Osmunda medium in either thumb pots or other community pots containing ten to fifteen plants. When this move has been com­pleted, they may be treated like adult plants, with only a bit more attention to watering, potting, and air conditions.

Growing orchids from seed is an arduous task, but growers who have had the experience will attest that blooms so produced bring a feeling of accomplishment unique in orchid culture.

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