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Chuck Kocher, of Pittsburgh Cut Flower, demonstrates orchid potting to groupof Penn State Floriculture students visiting greenhouses in Pittsburgh area.

A FLOWER GROWERS

BULLETIN 194 APRIL, 1967

The Latest on . . .Plant Diseases

Les Nichols

Plant Pathology Extension

THERMAL DUSTING AND A NEW FUNGICIDE

FOR CONTROL OF BOTRYTIS IN GERANIUM

Cutting rot caused by Botrytis is often a seriousproblem for the geranium propagator. The Botrytisfungus is commonly found on fading flowers of stockplants and on dead and aging plant tissue such as lower leaves, broken stems and on stubs from which cuttings had been taken. Under moist conditions, massesof thousands of spores are produced on the affectedtissue. The spores are very light and with changes inhumidity are dislodged, float through the air and mayfall on the "hairy" surface of the geranium stems(Figure 1). They lie dormant here until the cuttingsare taken and are stuck in the propagating medium.The moisture in the sand or soil causes the spores togerminate and they infect the cutting causing rottedspots on the sides or at the base (Figure 2). One ofthe main purposes of spraying the stock plants on aregular schedule with a fungicide such as captan orzineb is to place a protective coating of fungicide onthe stems to kill the Botrytis spores before they caninfect the cutting.

The captan or zineb sprays have given effectivecontrol of Botrytis but where stock plants are growingvigorously it is sometimes difficult to obtain good coverage under the lush foliage and masses of spores areformed on the stubs from which the cuttings have beentaken. Termil,0 a new fungicide applied as a thermal

Fig. 1. Diagram of Botrytis spores on surface of geraniumstem.

Fig. 2. Rotting of geranium cutting in propagating benchfrom Botrytis.

dust, has given thorough coverage of all parts of theplant and where used on a regular program has practically eliminated the Botrytis problem.

Termil contains 90.0% tetrachlorophthalonitrile theactive ingredient found in Daconil 2787. It is a specialformulation designed to sublime or vaporize withoutdecomposition when heated to a temperature of 600to S00°F. As the vapor cools, condensation occurs andvery fine dust particles of the Termil are deposited asa film on all portions of the plants. In initial tests witha geranium propagator in southwestern Pennsylvania,Mr. Robert Oglevee, it was found that weekly applications of Termil reduced cutting losses due to Botrytis infection by 4% or a grain in production of 40,000cuttings. It was interesting to note in this test thatwhen the year-old stock plants were ripped out scarcely a trace of the fruiting of Botrytis spores could befound. In a comparable test plot which had been

(Continued on page 8)

PENNSYLVANIA FLOWER GROWERS

Bulletin 194 April, 1967

Published monthly at 907 Glenn Circle South, State College,Pennsylvania 16801, by the Pennsylvania Flower Growers, 50North Main Street, Chalfont, Pennsylvania 18914. Second classmatter, postage paid at State College, Pennsylvania 16801.Subscripion rates: active members - $5.00 per year; all othersubscriptions - SI0.00 per year. Send all communications to thePublications Office or to the Executive Secretary, 50 North MainStreet, Chalfont, Pennsylvania 18914.

OFFICERS

PRESIDENT EARL L. WAGONERE. C. Wagoner's Sons, Beaver Falls, Pa. 15010

V.. PRESIDENT LEWIS REINIGERWin. D. Reiniger & Sons, Hatboro, Pa. 19010

TREASURER AND EXECUTIVESECRETARY HOWARD G. KRUPP

50 North Main Street, Chalfont, Pa. 18914

EDITOR JOHN W. MASTALERZ970 Glenn Circle South, State College, Pa. 16801

Second Class Postage Paid at State College, Pa., 16801

CLIMATE CONTROL IN THE GREENHOUSENorman D. Augsburger, Sales Manager

Acme Engineering 6- Manufacturing Corp.Muskogee, Okla.

Reprinted from Illinois Slate Florists' Assoc. Bulletin

Greenhouse air conditioning has brought aboutmany changes. I think most growers now recognizethat it has greatly improved production and qualitythereby contributing substantially to the profitableoperation of this type of business.

Many BenefitsIt has also increased the comfort of employees.

Some have said that the human comfort aspect hasbeen of as much benefit as anything else. I recall hearing growers say that they used to have their peoplework in the greenhouse until 10 or 11 a.m. in thesummer, then shift them outside during the heat of theday. Around 4 p.m. they again return to the greenhouse to work. With air cooling this procedure hasbeen reversed. Still other growers reported that theyused to have a lot of trouble in getting new employeesand experienced considerable labor turnover. Afterair cooling was installed, they sometimes had a waiting list! Certainly, the aspect of human comfort cannot be overlooked and adds to the efficient operationof a greenhouse.

I think you will also recognize that air conditioninghas brought about some rather drastic changes ingreenhouse operations and growing practices. It hasput many greenhouses in business during the summerseasons that formerly laid dormant, and it has changedthe types of crops that can be grown. It has morenearly stabilized the scheduling of crops and haschanged the watering procedures. Air conditioning hasalso brought about drastic changes in greenhouse design, lowered construction costs, and has made the useof plastic-covered greenhouses more practical.

Greenhouse Air ConditioningGreenhouse air conditioning was originally con

ceived of as a means to lower house temperature. Theprocess of evaporative cooling to achieve this alsoraised the relative humidity which is usually too low insummer. This increase in relative humidity is verybeneficial.

The sometimes used term, "washed-air cooling,"implies that the method also provides cleaner air. Insome areas clean air isn't a problem but in many othersit is. If you don't think the fan-and-pad system givesyou cleaner air, just go out and look at the pads sometime after they've been in use for a few months.

Air conditioning also provides a more positive andmore uniform air movement, and the benefits of thisare becoming increasingly apparent to growers.

Air conditioning has also permitted the use ofmuch higher light intensities (less shading) in greenhouses. In our early investigations in cooling systems,we used light meters to determine the average lightintensities within a greenhouse during the summer. Asyou know, considerable shading was the general practice to help control the temperature. Of course, inmany cases the light intensity was too low to achievegood growing. As a result, when another method oftemperature control became available the need forshading became less important and less was used toimprove growing conditions. This is not to say thatsome shading should not be used; in fact, the use ofsome shading is still beneficial in helping to controltemperature. But the amount of shading used in thepast is no longer necessary.

As is quite obvious, the heat that brings about aneed for air conditioning comes from the sun. In outerspace, sunlight will produce about 420 BTU'S persquare foot per hour (a BTU is approximately theamount of heat produced by the burning of an ordinary wood kitchen match). By the time the sun's rayspenetrate the upper atmosphere and reach the groundlevel in clear air, they are reduced to about 290 BTU'sper square foot per hour. In an industrial area or incoastal regions where there is smoke or water vaporin the air, the heat intensity is reduced to approximately 200 BTU's. As a result of this, the locality ofthe greenhouse will have a bearing on whether anyshading is used or not, and if so, how much.

Modification In Design Factors

The changes that air conditioning brought abouthad also made it necessary to modify the design factors for the cooling systems. For example with higherlight intensities generally being used, our calculationshave had to be modified to accommodate this condition. As time went on, we found that there were otheradjustments that needed to be made. No two growersgrow their crops in exactly the same way, the temperatures they want are different, and localities are not thesame. Consequently, it isn't possible to have one fixeddesign formula that applies to every condition. If wecan make compensations in the calculations to help asystem work better in a particular area, we do it.

The original calculations for a cooling system anticipated a temperature rise in the air, after it came intothe house through the wet pads, of about 7 degrees before it was exhausted by the exhaust fans on the opposite sides or end. Naturally, the more air used the less

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temperature rise you have. On the other hand, the lessair used the more temperature rise will result. I do notbelieve there is an absolute right or wrong temperature rise that the plants and the growing conditionswill tolerate. Economics also become a factor sincemore fans and a larger pad area are required to provide more air, resulting in a smaller temperature risewithin the house.

In general, the tendency among growers has beento want a more uniform temperature (less temperaturerise) which means more fans and a larger pad area.Also, many growers have preferred the use of higherlight intensities in their houses. Both of these conditions can be achieved by increasing the overall capacity of the cooling system.

Other Factors To Consider

The elevation of the greenhouse must also be considered in designing a cooling system. While this isnot a factor in Illinois, it certainly is in Denver wherethe altitude exceeds 5,000 ft. and in other similar areaswhere the air is less dense. The heat-carrying capacityof air is determined by its weight, not by its volume.The capacity of a fan is determined by the volume ofair it handles, not its weight. So if one doesn't allowfor extra air to provide the same pounds of air in acooling system at a higher elevation, the cooling won'twork as. well. This has sometimes been overlooked indesign calculations but will definitely show up if it isnot compensated for.

Another factor to consider in an air-conditioningsystem in a greenhouse is the velocity (speed of airmovement) of the air within a greenhouse. At first ourconcern in this regard was mostly related to peoplerather than to the plants. I recall being in a greenhouse that was 100 ft. long and equipped with a cooling system that worked just fine. The next year thesame grower decided to cool an adjacent house thatwas 200 ft. long. We used the proper amount of fansand pads, and the temperature rise from one end tothe other was exactly the same as in the shorter house.But, he complained that the system in the 100 ft. housedid not work as well as in the 200 ft. house. The difference was that the velocity of air movement in thelong house was twice as fast as that in the shorter one.In the 100 ft. long house, the average speed was approximately 100 ft. per minute—a little over 1 mile perhour (1 mph is 88 ft. per minute). However, the velocity in the longer house was about 200 ft. per minute,or approximately 2% mph (an average person walksabout 3 or 4 mph).

People are very sensitive to air velocity — this iswhy, in warm weather, one feels cooler in front of afan even though the air temperature is no different. Ina greenhouse cooling system, the velocity of the airHow is directly proportional to the distance from thepad to the fan. In the cross-flow system the pad-to-fandistance is usually quite short, therefore the velocitywill be quite low. And under these conditions, growerssometimes complained that the house felt clammy.

Actually, the temperature was satisfactory but thevelocity of the air was low which brought about thisfeeling. As a result of this, we have increased the calculation factors when designing a cross-flow system tohelp overcome this low-velocity airflow condition.

I have called to your attention a number of factorsthat effect temperature rise, as well as the psychological or apparent feeling of comfort from a cooling system. It is very important for one to understand someof these conditions so that a person can better appraisethe performance of cooling systems and thereby knowwhat to buy or what to expect in a cooling system.

How Much Cooling Can You Get?

Another point of interest is the temperature towhich one can cool the air by evaporative cooling.Theoretically, air can be cooled down to the wet-bulbtemperature. To give you some idea of what the wet-bulb temperature is, we might say it would be likestepping out of a shower or swimming pool and standing in front of a fan. For an instant, one's skin temperature will drop down very nearly to the wet-bulbtemperature. In actual practice, the wet-bulb temperature is not quite reached, but we can get to within 2 or3 degrees of it. This would be equal to a temperaturedrop of about 85% of the difference between the outside wet-bulb and dry-bulb temperatures.

There is considerable information available aboutwet-bulb temperatures throughout the United Stateswhich has been accumulated from records kept formany years. In fact, maps of the U.S. are availableshowing lines that represent the average maximumwet-bulb temperatures for the 4 hottest months. Inlooking at such a map, I can tell a man almost exactlywhat temperature he can expect his cooling system toreach during the hottest part of a summer afternoon.

The map I have here shows that the average maximum wet-bulb temperature in Southern Illinois is 77°F., in Central Illinois it is 76°, and in the Chicagoarea, 75°. Thus, there is only about a 2-degree difference in the available cooling capacity for a greenhousewithin this state. In fact, throughout most of theUnited States the range in wet-bulb temperature isonly about 10 degrees from the lowest to the highest,with the exception of high altitude regions. In thenorthern region of the country the average maximumwet bulb temperature is about 70°, while in the Gulfregion it goes to as high as 80° F. In certain highaltitude areas, such as Denver, the average maximumwet-bulb temperature is about 64°.

Bear in mind that I am talking about the normalmaximum wet-bulb temperatures during the 4 hottestmonths. Most of the time during these months thewet-bulb temperature is considerably lower, resultingin the ability to cool to a lower temperature. There isa lot more that could be said about wet- and dry-bulbtemperatures and their relationship to climatic conditions; this could be a completely separate subject ofdiscussion and time does not permit it now.

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Cooling Where The Plants Are

A proper greenhouse cooling system is designed tocool only the area where the plants are. Generallyspeaking, this covers the area from the gutter linedown to the floor. We are not interested in cooling theupper regions of the greenhouse since there are noplants there anyway and to do so would greatly increase the cooling load and require a lot more equipment.

To cool only the growing region requires that webring the air in through the pads that are properlypositioned and of adequate size. We bring the air inslowly in what we call a 'laminar flow" condition —meaning a very smooth flow without turbulance. Thiskeeps the cool air mass down in the growing regionwhere it docs its good. The air above this, in the ridgeof the house, becomes quite hot. And we want it toremain stationary to avoid its mixing with the coolmass of air below it. In fact, this stationary mass ofair overhead acts somewhat as an insulator and wecan help it stay stationary, particularly when drawingair lengthwise through a house, by installing plasticbaffles at periodic intervals. To let mixing occur wouldonly dilute the cool air and reduce the effectiveness ofthe overall cooling system of the greenhouse.

Winter Ventilation Another Problem

When we consider the fall, winter and spring seasons, the whole ventilation picture changes and requires a completely different approach than that usedfor summer cooling. Because of the great amount ofradiant energy received from the sun, the greenhousecan become much too warm on a bright sunny day,even though it is very cold outside. In fact, the outsideair which we need to bring in is often so cold that ithas to be handled in a very special way to avoid coldspots or drafts within the house if we want to achievecorrect cooling and ventilating.

Under such conditions, it is highly desirable tobring the air in through many small openings in orderto more uniformly distribute it and avoid a curtain orlayer of cold air in any one area. Many growers whohad summer cooling fans soon learned that by runningone or two of them in the wintertime they could leakin considerable air through the laps and joints in theglass panes. This provided very desirable ventilationand cooling throughout the house without cold spots.To better understand how this works, I think it wouldbe well to briefly discuss some of the principals ofaerodynamics and show how they are applied towinter ventilation of a greenhouse with fans.

Let us install an exhaust fan in a greenhouse walland turn it on. The fan immediately creates a slightvacuum in the greenhouse and this vacuum existsthroughout the entire greenhouse, not just at the fan.The air that goes to the fan does not come from animaginary shaft of air immediately in front of it butcomes to the fan from all directions, just as watermoves from all directions toward the drainhole in a

bathtub. Under this type of ventilation application, bythe time one moves about 1 or 2 diameters away fromthe fan you can hardly tell where the fan is. That iswhy it doesn't matter very much where the exhaustfan is located in the greenhouse, as far as winter ventilation is concerned. And that is why summer coolingfans can be used so effectively for winter ventilation.

I have just shown you how air approaches and goesthrough an exit hole which, in reality, was the exhaustfan. Now let us consider the behavior of air on the discharge side of the hole. In this case it would be the aircoming into the greenhouse from the outside due tothe vacuum that was created within the greenhouse.

The air comes into the house in the form of a jetand the distance it will travel is related to the speed ofthe air and the size of the hole. We want the air tocome in at a relatively high velocity, creating a lot ofturbulence around the jet and producing thoroughmixing with the warmer air within the house as quicklyas possible. Under normal conditions, the fans createa vacuum of Vi o to % of an inch vacuum which willproduce a jet having a speed of about 1,000 ft. perminute or 12 mph. This jet will travel from 20 to 30diameters of the hole size—which is not a very greatdistance when we are talking about an %- or %-inchcrack. Obviously, a hole 1 or 2 ft. square would produce a jet that would travel many feet into the greenhouse and be highly undesirable in the winter.

A high velocity jet, as mentioned above, will mixvery rapidly with the air in the greenhouse. Let's consider a greenhouse temperature of 60° F. and an outdoor temperature of 0°. By the time the jet travels 20or 30 diameters it will be warmed to within 5 or 6° ofthe greenhouse temperature. This is a very importantphysical phenomenon for growers to understand. Itshows that if air is brought in properly, cold drafts canbe completely prevented.

As a further demonstration of what I have just explained, I will smoke a cigarette and blow the smokeout of my mouth or nostrils. You can see that it comesout in the form of a jet, flows away a considerabledistance with a lot of turbulence, and quickly mixeswith the air in the room. When one takes a breath(inhales) through the nose, the air is drawn to thenostrils from all directions (just like it flowed to theexhaust fan.) But when one exhales through the nose,the air jets away from the face. This may sound a bitpeculiar but this principle of aerodynamics keeps onefrom suffocating in his own exhaled breath!

Plastic Tube Ventilation

Winter ventilation in older glasshouses wasn'tmuch of a problem in cold weather because one couldget enough air in through the cracks between theglass. However, winter ventilation becomes more of aproblem in newer tighter greenhouses, particularly inplastic houses where there are practically no holes orcracks. There was a very definite need for bringingair into the greenhouse through many little jets, ac-

cording to the principle just discussed. And that iswhere the idea began to grow for introducing airthrough plastic tubes having many punched holes.

This system consisted of a long plastic tube connected to the end wall of a greenhouse with a highefficiency streamlined inlet. When an exhaust fan wasturned on creating a vacuum in the house, the pressurein the house was lower than the pressure in the tubewhich was connected to the outdoors. Consequently,air rushed into the tube, inflated it, and flowed outthrough the many holes to be uniformly distributedthroughout the house. This resulted in uniform, draft-free ventilation. Depending upon the size of houseand the type construction, two or more tubes perhouse were often called for. At the present time threedifferent sized tubes are available to provide for morecomplete ventilation capacities.

The fresh air introduced in this way, even thoughquite cold, would be warmed up to house temperatureby the time the small jets of air were just a few feetaway from the tube. During its operation, the housewould maintain uniform temperatures. And at thesame time, good air movement was produced that wasconsidered very beneficial to growing conditions. Thesystem could be run automatically, saved considerablelabor, and produced better and more uniform ventilation than was generally available before.

Benefits of Continuous Air Movement

As a result of the desirable air movement producedthrough fan-and-pad cooling in summer and the absence (or at least a much lesser amount) of it in winter,many growers became much more conscious of theneed for providing and maintaining good air movement within the greenhouse during the wintermonths. It was felt that this would greatly improve themicroclimate around the plants. And it also pointedup the need for more uniformity of house temperatures and humidity levels.

This led to some rather amazing information weobtained by making field tests on the climatic conditions within a greenhouse.

We measured the temperature and relative humidity in the aisles and then in the benches where thecrop with dense foliage was growing. As you know,the plants were giving off moisture while the aislesweren't. In many cases, the relative humidity downaround dense foliage would be 30 to 35% higher thanthat measured in the aisle. I am sure a lot of disease

problems that growers encounter have been due to toohigh humidity around the plants—much higher humidity than in the aisle where a reading would bemost likely be taken since that is about the only placea sling psychrometer can be manipulated. This definitely indicated a need for improved air circulationwithin the house to equalize the humidity and reducethe level around the plants. As a result, Turbulatorair-circulating fans were introduced to achieve desirable air motion in the greenhouse.

Effect Of Temperature On Relative HumidityThis leads us to another point which growers

should understand and which can be of great benefitto them: the effect of temperature on relative humidity. Air has the ability to absorb moisture. And theamount of moisture contained in air in relation to howmuch moisture this same air could actually hold is referred to (in terms of percent) as the relative humidity.Therefore, air having a relative humidity of 50% contains only half as much moisture as it actually could.Temperature has a very drastic effect on the amountof moisture air can hold. For every 20° rise in temperature, the amount of moisture air can hold willdouble. For example, if one takes air at 40° F. and at100% relative humidity and warms it up to 60°, itsrelative humidity will have dropped to 50%. If thissame air is warmed another 20°, its relative humiditywill drop down to 25%. I am sure many of you can seefrom this that in so-called humid areas the relativehumidity becomes quite low on a hot summer afternoon. This drying action, achieved by raising the temperature of air, is actually what some rose growershave taken advantage of when they turn on a littleheat in the early morning to dry out the house andprevent mildew problems.

This is a very important principle to keep in mindwhen you want to do something about reducing thehumidity in your greenhouse. Bring in some cold outside air (even though it might be raining), and heat itup by mixing it with the warmer air in the house. Byso doing you can reduce the relative humidity withinthe greenhouse. A psychometer chart completely explains this phenomenon and would be exceedinglyhelpful to growers.

A Combination System—Ventilation And Air Circulation

I have briefly covered the apparent need for moreeffective air movement and circulation within a greenhouse during the colder months and satisfactory waysfor bringing in fresh air. This brought about the concept of a combination system; namely, one that wouldachieve both. Instead of connecting the plastic tubeto the outside wall, we attached it to a special fan thatwas positioned approximately 15 inches from the outside wall. The fan, in turn, was positioned directly inline with an inlet shutter that was installed in the end

wall of the house.

When the tube fan is turned on, it immediately inflates the tube and distributes air throughout the housefor the full length of the tube. But when the inletshutter in the end wall of the house is closed, the fanmerely recirculates the air within the house to maintain a more uniform temperature and to give betterhumidity control. Furthermore, if one is feeding CO^,it is also evenly distributed with this system.

When the house temperature gets too warm, themotorized inlet shutter in front of the tube fan is automatically opened by a thermostat which also turns on

(Continued on back cover)

6 —

PENN STATE STUDENTS VISIT GREENHOUSES

Bob Blind (right) discusses how college training and practicalexperience are combined to grow crops successfully.

Students receive some very valuable pointers from Fred Ilinckel(center) on producing a variety of flower crops.

Chuck Kocker (the man in the white hat) talks about the problems and decisions a managermust make to operate one of the largest greenhouse ranges in Pennsylvania.

PENN STATE

BEDDING PLANT

MANUAL

Published by

PENNSYLVANIA

FLOWER GROWERS

COPIES AVAILABLE

from

J. W. MASTALERZ101 Tyson Bldg.

University Park, Pa. 16802

Please make Checks

Payable to:

Pennsylvania Flower Growers

HENRY F. MICHELL CO. KING OF PRUSSIA, PA.

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PENNSYLVANIA FLOWER GROWERS

50 NORTH MAIN STREET

APRIL, 1967

BULLETIN 194

CHALFONT, PA. 18914

GREENHOUSE CLIMATE CONTROL-(Continued from page 6)

an exhaust fan somewhere else in the house. The

vacuum created by the exhaust fan draws fresh air inthrough the inlet shutter which jumps directly into theblades of the tube fan and is propelled down the tube.This fresh, cool outdoor air is evenly distributedthroughout the house and lowers the temperature uniformly until the thermostat is satisfied. It then turnsoff the exhaust fan and closes the inlet shutter. Mean

time, the tube fan continues to run, maintaining constant recirculation within the house.

This same method of control using a humidistat canhelp regulate the relative humidity within the houseduring cool weather. By bringing in fresh outdoor airwhich is warmed by mixing with air within the house,the relative humidity is lowered. It is truly amazingwhat humidistats and thermostats can do.

About Plastic Tubing

We are also using a higher quality polyethylenetubing in an effort to obtain longer life. Since greenhouse glass filters out most of the ultra-violet rays ofthe sun, polyethylene tubes should last longer in thesehouses than in plastic-covered houses which do notfilter out the ultra-violet rays as well. Shading fromthe tubes is usually not significant, unless they becomequite dirty. Because plastic films develop a staticcharge, they do attract dust rather quickly and mayneed to be changed because of the dirt they attractlong before they are worn out or otherwise deteriorate.

Plastic tubing is now available in three differentdiameters: 18 inch, 24 inch, and 30 inch. Normally, itisn't wise to put a single tube in a house if it is over30 ft. wide since you will begin to lose the effective airdistribution considered so beneficial. The holes in thetubing are arranged in two rows, one on each side andslightly below center. This arrangement allows the airto flow in a downward and outward direction, at aboutthe same angle as the roof line, and yet not directlydown on the plants.

I might also point out that our Fan-Jet tube fan is

Second Class Postage Paid at

State College, Pa.

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fitted with stators (sometimes known as stationary fins)in its discharge orifice which direct the air flow straightdown the tube and eliminate the violent spinning andturbulence that would otherwise tend to occur.

In the past there has also been considerable troublein suspending or hanging the plastic tubing. It wasquite a chore to thread a wire down through tubingfor its entire length, and grommet tapes did not alwayswork out too well.

A special new tube hanger has recently been developed and placed on the market which has been highlysuccessful. It is a non-slip plastic clip that securelygrips the tubing; it is reusable and should last forseveral years. We have already had inquiries aboutthe possibility of using this hanger for shadecloth andother applications. The recommended spacing forthese tube hangers is 10 ft. for 18-inch tubing, 8 ft. for24-inch tubing, and 6 ft. on 30-inch tubing. With 4-miltubing this would amount to about 1 pound of weightfor each tube hanger.

Automation Justified — EssentialThe subjects I have discussed with you are not

gimmicks or pipe dreams, but a reality. These systemsare in actual use and can do many things for you. Youhave heard from other speakers today about the needfor greater savings in labor and your other costs ofoperation. The more automated you can become inclimate control, the more you will save in time andlabor.

This equipment will more than pay for itself in arelatively short period of time. And it will provide youwith a much better climate control system than youyourself could achieve by doing it manually.

Agriculture in this country is highly automated, infact, one of the most highly automated industries today. In the floriculture industry you have alreadyadopted many automated or semi-automated practices,such as automatic watering, injection fertilizing, mistpropagation, and automatic lighting. Why not alsotake advantage of automatic summer cooling and automatic winter ventilation? In just a matter of time youwill wonder how you ever got along without it.