Program

Lynn O'Shaughnessy

Natural Light Photography

Meeting:

· Bring plants for show and tell

· We will have an auction

· Lynn will have plants for sale – see below

Meeting:

Lynn has been a pleurothallid addict since 1997. She started out growing pleurothallids under lights in her basement and eventually moved to her new greenhouse in January 2000. With more growing space available, she has been venturing into hybridizing and growing seedlings from flasks and compots. She has over 1,400 plants in her personal collection in nearly every genera of Pleurothallids, including many divisions and kiekis.

Lynn has been doing photography for over 30 years. She studied nature photography with leading nature photographers, John Shaw and Larry West. She is the Great Lakes Judging Center photographer. She is the webmaster for www.pleurothallids.com, which has over 1,500 photos. She prefers doing natural light photography. She uses 25-year old Canon cameras, nothing automated.

Photos featured will be of many genera of orchids, not just pleurothallids

She will bring some pleurothallids to sell. Anyone who wants to pre-order can visit her sales pages at

http://www.pleurothallids.com/lynn's_sales_list.htm and

http://www.pleurothallids.com/lynns_sales_list2.htm

She will give a 10% discount on pre-orders

TREASURER’S REPORT:

August 20, 2003

Meeting dates and rooms

All meetings are scheduled for room 1510 EXCEPT the January 2004 meeting which will be in Room 4380

Email Address?

If you have an email address, and you are not getting the newsletter via email, please send the address to me. It is much easier, faster and less expensive to get the email version to you! My email address is glf@proinnovation.com

Officers President: John Talpa 269 649-4340 jtcompany@bizloop.com; Treasurer: Ginnie Hessler 269 382-3824 tivth@sbcglobal.net; Secretary Greg Filter 269 -979-7626 or 269 -979-7974 Greg Filter; Program: Russ Hibbard & Georgiann McWilliams call: or FAX 269 685 2268 or 269-685 1167, fax 1 269 685-6506, email, georgiann@charter.net Refreshments: Ginnie Hessler 269 382-3824
Web Site Address: http://www.proinnovation.com/dko

Refreshments: Ginnie Hessler; We need volunteers for the upcoming year – come prepared to volunteer!!

http://nat_hist.sdstate.edu/orchids/pests/scales.htm

Scale Insects on Orchids*

Paul J. Johnson

Insect Research Collection,

Box 2207A, South Dakota State University,

Brookings, SD 57007

This note is written for the orchid keeper or grower in northern states of the U.S., and Canada, that generally has a small to medium sized indoor collection. The keeper or grower in southern states enjoys the potential of many more scale problems because of outdoor growing, but also benefits from natural environmental population management by the weather, and predatory and parasitic enemies of scales!

Sources and Identification

Scales are probably the most important insect pests of cultivated orchids in northern climates. Mealybugs and aphids may tie for second in importance and are controllable with the same methods. According to a 1976 publication from the Florida Department of Agriculture and Consumer Services, there are no fewer than 27 species of scale identified from cultivated orchids. Fortunately, few hard or armored scales, but mostly soft scales, usually referred to as brown soft scales or hemispherical scales, regularly survive in the north on indoor or greenhouse plants. Especially common is the brown soft scale (Coccus hesperidium) shown above, and possibly the similar elongate soft scale (Coccus longulus). Boisduval’s scale (Diaspis boisduvali)[, , , the scurge of the southern orchidists, is rarely encountered in northern home collections and apparently does not survive well here, except in the largest greenhouses.

The more common species of these odd insects that infest orchids are immediately recognized in the adult stage by the light yellowish to greenish-brown, tan, or dark brown, oval to circular, objects that show-up on leaves, petals, sepals, petioles, pseudobulbs, and sometimes rhizomes and roots. Mature females of Boisduval’s scale are a rather typical rounded and light-colored scale type, while males are easily recognized by the cottony appearance of aggregated males, and these may be confused with mealybugs if not examined closely. The immatures, or crawlers (above far-left), of all scale species are tiny and yellowish to pinkish, and not easily seen without a magnifier.

In the home orchid collection scales are aquired by your plants in some combination of three sources. The most common way of acquiring scales is by purchasing an infested plant. On plants at home scales are easily transmitted from infested to clean plants when your plants touch each other and the crawlers to move from plant to plant. The final source is colonization of your plants by windblown crawlers. Colonization is usually done during the summer when your plants are outdoors, but it can also occur indoors in greenhouses and sunrooms by floating on currents produced by circulating and heater fans. This occurrence appears to produce the odd effect of having pockets of infestation when the crawlers settle on plants where the air currents are the weakest and early during a spreading infestation. Similar effects are found with aphids, mealybugs, whiteflies, and spider mites.

Life Cycle

Scale insects have a three-stage life history: egg, larva (or nymph), and adult. Eggs are laid by females, with the eggs usually retained in the body and under the outer “scale” covering when the female dies. These hatch into the mobile nymphs, called crawlers. The crawlers are the active stage that can move between plants. After finding a suitable place for feeding, the crawler will settle and begin feeding, and transform into the next nymphal stage. At this point the female begins to form the hard protective “scale” covering. The covering enlarges as the insect grows. Nymphs often have a light yellowish scale, which darkens to tan or brown as the insect matures. Males of soft scales do not form the hard coating or scale, but are small winged creatures whose primary, if not sole, role is to mate and die.

Scales have short life cycles, but may cycle many times a year. In a warm greenhouse or indoors the life cycle may be accelerated, though typically a month or more is required for completion of a generation. It is the overlapping of generations that creates the biggest scale management problem. All control methods are at their greatest effectiveness against the the crawlers. By the time the scales have formed the hardened cover (the scale), it is too late to easily kill those adults with chemicals. Also, the large dry brown scales are already dead and the “shells” may be full of eggs (if they are full of a fine powder-like substance, then they were probably killed by a chemical treatment).

*Updated from the November 2000 issue of the Newsletter of the South Dakota Orchid Society.

Continued next month…