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Pear, common -fPyrus communis 4, 32

Pear, sand ; Pyrus pyrifolia 32

Pearlbush, Exochorda 20

Pea-tree, Caragana arborcsceus 4. 15

Pecan, Carya Pecan 4. 15

Pepperbush, sweet ; Clcthra ainifolia 4, 17

Periploca graeca L., silk-vine 28

Pcriplocd scpium Bge 28

Philadclphus spp., mock-orange 3, 28

Philadelphn^s coronarius L 10, 28

Philadelphus cymosiis Rehd 28

Philadelphus grandiiiorus Willd 28

Photinia glabra (Thunb.) Maxim 28

Pbofinia sarrulata Lindl 28

Photinia villosa ( Thunb. ) DC 4

Physocarpus opulifolius (L.) Maxim., ninebark 28

Picea Abies (L.) Karst., Norway spruce 4, 8, 11, 28

Picca glauca ( Moench.) Voss. var. conica Rehd 10, 29

Picea 0))iorika ( Pancic) Purkyne, Serbian spruce 29

Picca pungcns Engelm., Colorado spruce 7, 29

Picca sitchciisis (Bong.) Carr., Sitka spruce 29

Picris floribunda ( Pursh. ) Benth. & Hook 29

Pieris japonica ( Thunb. ) D. Don 29

Pine, Austrian ; Pinus nigra 30

Pine, lace-bark ; Pinus Bnngcana 30

Pine, Scots ; Pinus syltvestris 30

Pine, white ; Pinus Strobus 2, 4, 10, 29

Pinus Bungcana Zucc, lace-bark pine 30

Pinus nigra Arnold, Austrian pine 30

Pinus Strobus L., white pine 2, 4, 10, 29

Pinus sylvestris L. Scots pine 30

Plum, Prunus 30, 31

Plum, beach ; Prunus maritima 31

Plum, cherry ; Prunus cerasifera 4, 6, 30

Poncirus trifoliata ( L. ) Raf 30

Poplar, black ; Populus nigra 30

Poplar, white ; Populus alba 30

Populus spp 9, 30

Populus alba L., white poplar 30

Populus dcltoidcs Marsh., Cottonwood 30

Populus grandidcntafa Michx., large-toothed aspen 30

Populus nigra L., black poplar 30

Populus ircnniloidcs Michx., quaking aspen 30

Potentilla fruticosa L 4, 30

Privet, California ; Ligustrum ovalifolium 4, 6, 25

Privet, Japenese ; Ligustrum japonicum 6, 25

Prunus cerasifera Ehrh.. cherry plum 30

Prunus glandulosa Thunb.. dwarf flowering almond 31

Prunus incisa Thunb - , 31



54 MASS. EXPERIMENT STATION BULLETIN 382

Page

Primus japonica Thunb 31

Prunus Laurocerasus L., cherry laurel 31

Prunus maritima Marsh., beach plum 31

Prunus Padus L., European bird cherry 31

Prunus pseudoccrasus Lindl 31

Prunus subhirtclla Miq., Higan cherry 31

Pntnus tomentosa Thunb 31

Prunus triloba Lindl., flowering almond 31

Pscudotsuga taxifolia (Poir.) Brit., Douglas-fir 31

Pterocarya stenoptera DC 31

Pueraria Thunbergiana (Sieb. & Zucc.) Benth., Kudzu-vine 31

Pyracantha atlantioidcs ( Hance) Stapf 32

Pyracantha coccinca Roem 4, 5, 32

Pyracantha crcnulata (Roxb.) Roem 32

Pyrus communis L., common pear 32

Pyrus pyrifoiia (Burm. ) Nakai, sand pear 32

Quercus borealis, Michx. f ., red oak 32

Qucrcus robur L., English oak 32

Quince, Cydonia oblonga 19

Quince, Japan ; Chacnoniclcs lagenaria 2, 10, 16

Raspberry, Rubus 8, 36

Redbud, Ccrcis 16

RJianinus, buckthorn 3, 4

RJwdodoidron arbor cscens (Pursh) Tort 2>2i

Rhododcndroji calc7idii!aceum (Michx.) Torr 33, 34

RJiododcndroii canadcnse (L.j Torr., rhodora 33, 34

Rhododendron cancsccns (Michx.) Sweet 33

Rhododendron Collctiianuni Aitch 33

Rhododendron dauricuni L 33

Rliododendron gandavcnse (K. Koch) Rehd., Ghent azalea 33

Rlwdodendron hirsutum L 33

RJiododendron indicmn (L.) Sweet 32

Rhododendron japonicuin (Gray) Suringar 32

Rhododendron laetevirens Rehd 32

Rhododendron lapponicum Wahlenb 32

Rliododendro)! maximum L 32

Rhododendron micranthum Turcz 33

Rhododendron minus Michx 3"?

Rhododendron mixtum Wils 33

Rhododendron molle ( Bl.) G. Don 33

Rhododendron mucronatum G. Don 33, 34

Rhododendron mucronulatuin Turcz 33, 34

Rhododendron nudMorum (L.) Torr., pinxter flower 33

Rlwdodendron obtusum (Lindl.) Planch 33. 34

Rhododendron obtusum (Lindl.) Planch, var. japonicum (Maxim.) Wils. 33

(includes Kurume azaleas)

Rhododendron obtusum (Lindl.) Planch, var. Kaempferi (Planch.) Wils. 33

Rhododendron ponticum L 33

Rhododendron pulchrum Sweet 33, 34

Rlwdodendron raeemosuin Franch 32

Rhododendron reficulatuni D. Don 33

Rhododendron roseum (Loisel.) Rehd 33

Rhododendron Schlippenbachii Maxim 33

Rhododendron Vascyi Gray 33

Rhododendron viseosepalum Rehd 33, 34

Rhododendron fuiscoswn (L.) Torr., clammy azalea 33

Rhododendron yedoense Maxim, var. poukhanensc (Levi.) Nakai .... 33, 34

Rhododendron yunnanense Franch 32

Rhodora, Rhododendron canadensc 33, 34

Rhodotypos scandcns ( Thunb.) Mak 34

Rhus aromalica Ait., fragrant sumac 34

Rhus typhina L., staghorn sumac 34

Ribes spp., currant 3

Ribcs alpinum L., alpine currant 34, 35

Ribes Grossularia L 35

Ribcs nigrum L., European black currant 34

Ribes rnhrum L., northern red currant 34



PROPAGATION OF TREES AND SHRUBS 55

Page

Ribes sativum Syme., garden currant 34

Rohinia Pscudoacacia L., black locust 35

Rosa spp 35

Rosa Hugonis Thunb 35

Rosa multiflora Thunb 35

Rosa oineiciisis Rolfe 35

Rosa riigosa Thunb 35

Rosa sctigera Michx., prairie rose 35

Rose, hardy climbing 35

Rose, hybrid perpetual 35

Rose, hybrid tea 35

Rose, prairie ; Rosa sctigera 35

Rubus, raspberry 36



garden ; Salvia officinalis 36

St. John's-wort ; Hypericum 22

Salix alba L., white willow 26

Salix discolor Muhlenb., pussy willow 36

Salix Elacagnos Scop 36

Salix hcrbacca L., dwarf willow 36

Sak'ia officinalis L., garden sage 36

Saiiibucus canadensis L., American elder 36

Sanibucus vielanocarpa Gray 36

Sanibucus nigra L., European elder 36

Sanibucus racemosa L., European red elder 36

Sav'mJwiipcrus Sabiiia 23. 24

Sciadopitys vcrticillata (Thunb.) Sieb. & Zucc, umbrella-pine 2>'o

Securinega stiff I'liticosa ( Pall. ) Rehd 36

Senna, scorpion ; Coronilla Emerus 18

Shadbush, Amclanchicr 14

Silk-vine. Periploca graeca 28

.Silverbell-tree, Halcsia 21

Smoke-tree, Cotinus Coggygria 34

Snowberry, Syniphoricarpos albus 27

Snowberry, creeping ; Chiogenes hispidula 17

Sorbaria sorbi folia ( L. ) A. Br 36

Sorrel-tree, Oxydcndrum arboreum 27

Spice bush, Lindcra Benzoin 25

Spindle-tree, Euonynius 20

Si)indle-tree, European ; Euonymus europaea 20

Spindle-tree, winged ; Euonymus alata 20

Spiraea arguta Zab 36

Spiraea Billiardii Herincq 36

Spiraea Bunialda Burvenich 36

Spiraea salicifolia L 36

Spiraea Thunbergii Sieb 36

Spiraea Vanhouttei ( Briot) Zab 36

Spruce, Colorado ; Picea pungcns 7, 29

Spruce, Norway ; Picca Abies 4, 8, 11, 28

Spruce, Serbian ; Picea Omorika 29

Spruce. Sitka ; Picea sitchensis 29

Staphylea, bladdernut 3

Sfeplianandra incisa (Thunb.) Zabei 36

Stephanandra Tanakae Franch 36

Stczvartia koreana Rehd 36

Stezi'artia ovata (Cav.) Weatherby 36

Strawberry-bush, Euonymus anicricana 20

Styrax anicricana Lam 2)7

Styrax japonica Sieb. & Zucc 37

Styrax Obassia Sieb, & Zucc 27

Sumac, fragrant ; Rhus aromatica 34

Sumac, staghorn ; Rhus typhina 34

Sun-rose, HcUanthemum 22

Sweet-gum, Liquidanibar Styracifluci 26

Sweetleaf, Asiatic ; Symplocos paniculata 2, 11, 27



56 MASS. EXPERIMENT STATION BULLETIN 382

Page

Syinphoricarpos albiis Blake, snowberry 2)7

Symphoricarpos orbiculaius Moench, coralberry 2i7

Symplocos paniculata (Thunb.) Miq., Asiatic sweetleaf 2, 11, 2>7

Syringq emodi G. Don, Himalayan lilac 38

Syringa Henryi Schneid 38

Syringa Josikaca Jacq., Hungarian lilac 38

Syringa persica L., Persian lilac 38

Syringa Prestonae McKelvey 8

Syringa tomcntella Bur. & Franch 38

Syringa villosa Vahl 38

Syringa vulgaris L 3, 37

Tamarisk, Tamarix* 3, 38

Tamarix odessana Stev 38

Tamarix pentandra Pall 38

Taxus baccata L., English yew 6, 38

Taxus canadensis Marsh., Canada yew 6, 38

Taxus cuspidata Sieb. & Zucc, Japanese yew 6, 9, 10, 12, 38

Taxus media Rehd 7, 8, 10, 11, 38

Thuja occidcntalis L., American arbor-vitae 7, 10, 11, 38, 39

Thuja orientalis L., oriental arbor-vitae 39

Thuja plicata Lamb., giant arbor-vitae 38, 39

Thujopsis dolabrata (L. f.) Sieb. & Zucc, Hiba arbor-vitae 39

Triptcrygium Regclii Sprague & Tak 39

Trumpet-vine ; Cainpsis radicans 3

Tsuga canadensis (L. ) Carr., common hemlock 39

Tsiiga Sieboldii Carr 39

Tulip-tree, Liriodendron Tulipifera 26

Ulmus americana L., white elm 2, 4, 39

Ulmus parvifolia Jacq., Chinese elm 39

Ulmus puniila L., Siberian elm 39

Umbrella-pine, Sciadopitys verticillata 36

Vaccinium corymbosuni L., highbush blueberry 40

Vaccinium Vitis-idaea L., cowberry 40

Viburnum spp 3

Viburnum acerifolium L., dockmackie 10

Viburnum alnifolium Marsh., hobble-bush 40

Viburnum Carlesii Hemsl 10, 40

Viburnum, dentatum L., anow-wood 40

Viburnum fragrans Bge 40

Viburnum Opulus L., European cranberry-bush 40

Viburnum rhytidophyllum Hemsl 40

Viburnum Sieboldii Miq 4, 40

Viburnum tomentosum Thunb 8, 40

Vitex Agnus-castus L., chaste-tree 40

Vitex Negundo L 40

Vitis, grape 41

Vitis rotundifolia Michx., muscadine 41

Wcigela Horibunda (Sieb. & Zucc.) C. A. Mey 41

IVcigela iiorida (Sieb. & Zucc.) A. DC 4, 41

Willow, dwarf ; Salix herbacca 36

Willow, pussy ; Salix discolor 36

Willow, white ; Salix alba 36

Wing-nut, Pterocarya 31

Wistaria, Chinese; Wisteria sinensis (Sims) Sweet 8, 41

Wistaria, Japanese ; Wisteria floribunda (Willd.) DC 41

Wisteria, wistaria 3, 41

Witch-hazel, Hamamelis 22

Yaupon, Ilex vomitoria 23

Yellow-wool, Cladrastis lufea 17

Yew, Canada ; Taxus canadensis 6, 38

Yew, English ; Taxus baccata 6

Yew. Japanese ; Taxus cuspidata 6, 9, 10, 12, 38

Publication or this Document App»ovbd bt Couuissiom oh Aduinistration and Finance
6m-3-41— 5731



MASSACHUSETTS
AGRICULTURAL EXPERIMENT STATION

Bulletin No. 383 March, 1941



The Sanitary Evaluation of
Private Water Supplies

By Ralph L. France



A safe water supply for rural homes is of prime importance. This is an
explanation of some of the problems involved, with special attention to
contamination and its detection.



MASSACHUSETTS STATE COLLEGE
AMHERST, MASS



THE SANITARY EVALUATION OF PRIVATE
WATER SUPPLIES

By Ralph L. France, Assistant Research Professor of Bacteriologjy.



Introduction



Water is a prime factor in the support of all forms of life. While not
classified as a food, yet it is a necessary item in the diet. The value
of an abundant and pure water supply has been known from remote times.
Hippocrates, some four hundred years before the beginning of the Chris-
tian era, wrote that a polluted water should be boiled and filtered before
it was used for drinking — certainly a most up-to-date piece of advice.

Centers of population spranp: up around places where water was avail-
able. Where it was not available, extraordinary means were taken to
transport it. In Egypt and India today are to be found ruins of what
must have been great hydraulic works. Some were constructed at least
two thousand years before Christ. The great aqueducts of Rome were
built some few years before the Christian era. When one reflects that
these works of antiquity were constructed before the advent of steam,
electricity, and explosives, one is impressed with the great intelligence
and perseverance exhibited by these early engineers.

The fact that water can intensify and spread certain diseases was sus-
pected long before the discoveries of Pasteur and the germ theory of
disease. As the knowledge of bacteriology and sanitation has been ad-
vanced by new discoveries, the number of epidemics caused by contam-
inated water has been gradually reduced. In spite of the present advanced
knowledge in sanitation and water works practice, some epidemics of
typhoid and dysentery still do occur. In most cases they can be traced
to a lack of alertness, or a lack of proper application of modern knowledge,
on the part of those responsible for the purity of the supply.

It is the object of this bulletin to discuss rural private water supplies,
laying particular stress on the possibilities of their becoming contaminated
with disease producing bacteria; to explain the type of test used in the
laboratory to detect contamination; and to analyze the results of more
than 1,000 tests made during the past ten years on rural private water
supplies located in this State.

Classification of Water

"For practical purposes water may be classified as clean, polluted, or con-
taminatcd. (1) A clean water is one which at all times is free from contam-
ination or pollution, and safe for human consumption, as determined by
laboratory analysis, sanitary survey, and continued use. (2) A polluted water
is one which has suffered impairment of physical properties through the
addition of substances causing turbidity, color, odor, or taste. (3) A
contaminated water is one which carries potential infection by reason of the
addition of human or animal wastes, or has been rendered unwholesome
by poisonous chemical compounds." (Rosenau — Preventive Medicine and
Hygiene, 6th ed., 1935).



4 MASS. EXPERIMENT STATION BULLETIN 383

According to their sources, waters are classified as rain water, surface
water, or ground water. (1) Rain water is really a "distilled water";
that is, a water that has been vaporized and condensed. Distillation is
one of the best-known methods for purifying liquids. Thus, if properly
collected, rain water should be the purest type of water.

(2) Surface waters, i. e., ponds, creeks, rivers, lakes, etc., vary greatly
in composition and are subject to impurities. From a sanitary standpoint
they are the most dangerous type of water to be used for drinking. Most
cities in America depend upon surface water for their supply. It is hardly
possible in a populous country to obtain any great amount of surface water
free from contamination with human wastes. It is for this reason that
the modern water-treatment plant has been constructed. Ry the use of
filtration and chlorination these plants render the water safe for human
consumption.

In reality, streams are the natural sewers for the regions they drain.
It is inadvisable to use surface water as a source of supply without first
treating it to remove impurities.

(3) Ground water is the type almost universally used as a source of
supply for rural homes. It is usually satisfactory as far as impurities go.
As water percolates through the soil certain impurities are reinoved by
the natural filtering properties of the soil. The soil can take care of a
large amount of impurities if not over-burdened, or if tliere are no cracks
or crevices.

When water soaks into the soil it will finally come to rest upon an
impervious stratum. With its downward motion finally stopped, it then
spreads out in a horizontal plane, forming what is known as the ground
water tabic. This ground water table underlies practically all the earth's
surface.

Ground water may be divided into tliree types depending upon the depth
at which it is tapped, (a) Spring water is ground water that comes out
on the surface because of the topography of the land. Spring water does
not necessarily diflfer in composition from other types of ground water.
It is of a high degree of purity and can be easily utilized if it has a good
flow. Spring water, liowever, can easily become contaminated unless
proper precautons are taken to protect it. The protection of springs
against contamination requires a careful study of each location.

(b) Shallow well water is obtained from a source in which the ground
water table is very near the surface. It is perhaps the hardest type of
well water to protect from contamination, particularly in a dug well.

(c) Deep well water is that usually obtained at a depth of 50 or more
feet. It is generally the purest of ground waters, and the easiest to protect
against contamination. Artesian wells are of this type. The water is
mostly obtained by suction pumping or by means of compressed air.

Contamination of Water Supplies

The greatest hazard to man in drinking water is found in a water con-
taminated with the discharges from the human body, i.e., feces, urine, and
sputum. There is really little danger from water containing the waste materials
from other animal life, for the reason that few of the diseases contracted
by the lower animals are transmissible to man. There is still less danger
from organic matter of plant origin.



PRIVATE WATER SUPPLIES 5

The only diseases which in this State may be contracted by drinking con-
taminated water are typhoid fever and dysentery. There has been some sug-
gestion that jaundice might be transmitted in this manner but proof of this is
lacking.

Now the chance in this State of contracting typhoid or dysentery from any
source whatsoever is about 1 in 500,000. The Massachusetts State Board
of Health, in their Annual Report for 1939, list only 78 cases of typhoid
fever as occurring in the entire State for that year. The total number of
dysentery cases for the same period was 491. This latter figure may seem
rather high but further study of the Report shows that most were of
epidemic form and located in institutions.

In a personal communication from Dr. Roy F. Feemster, Director of
the Division of Communicable Diseases, the following comment is made:

We make a careful investigation of each case of typhoid fever
and bacillary dysentery and there is little in our records to indicate
that any of the cases in 1939 or in the years immediately preceding
were contracted because of contaminated private water supplies.
Bacillary dysentery may occasionally be transferred in this way
but I have considerable doubt as to whether any of our typhoid
cases result from the drinking of contaminated water. You will
be interested to know that practically all of our typhoid cases
occur singly and it is hard to believe that a water supply could
cause one case in a family and not afifect other individuals using
water from the same source. The reason for this condition can be
attributed to a number of factors, among them the alertness of
people of this area to make sure that water supplies are satisfac-
tory and the fact that we are in a glacial region containing sand
which acts as a natural sand filter.

To these reasons we would add another rather obvious one. In the
case of any water supply the only persons capable of contaminating that
supply are those living in its immediate vicinity. If none of these persons
contracts typhoid or dysentery from an outside source, or if none of these
persons is a carrier of the disease organisms, then it is practically im-
possible for such bacteria to gain access to the supply. Even if the
drainage from a cesspool, backhouse, or any other sewage disposal system
were to run directly into the well, it would still be practically impossible
for persons drinking the water to contract typhoid or dysentery from that
water.

The floods of 1936 present a fine illustration of the fact that the chances
of contracting disease from drinking contaminated water are, in this State,
practically nil. In our knowledge hundreds of wells were inundated with
polluted flood water. In many cases the water was used for drinking
before health authorities had the chance to purify the water. Yet no case
of typhoid fever resulted from these conditions.

However, even if a contaminated water may not cause a specific disease,
no one cares to drink it. Whether the contamination is of human or
animal source makes little difference; it is not a desirable water for human
consumption. There is some evidence to indicate that while water con-
taining sewage material may not cause a specific disease, it may cause
intestinal upsets of varying intensity. It is here that the laboratory test
renders its greatest service, for this test is designed to detect minute
amounts of sewage material rather than actual disease-producing bacteria.



6 MASS. EXPERIMENT STATION BULLETIN 383

The Laboratory Test

Most uninformed persons seem to think that all the bacteriologist has
to do to determine the purity of a water is to put a drop of it on a glass
slide and look at it through a microscope, and that if any typhoid or
dysentery bacteria are present they would be seen and recognized. Bac-
teriologists wish it were as simple as that. But it is not, and for the
following reasons:

In the first place, it would be impossible to concentrate water to the
point where a single drop would contain sufificient bacteria to be seen.

In the second place, under the microscope bacteria can be identified
only by the following general shapes and formations:

1. Spirilla. Here the cells are spiral, or corkscrew-like, in appearance.

2. Cocci. These cells are spherical in shape and appear in the follow-
ing formations:

a. Staphylococci, bunched like grapes.

b. Streptococci, in chains of varying length.

c. Diplococci, in pairs.

d. Some other formations which need not be mentioned here.

3. Rods. Here the cells are somewhat rectangular in shape.

It is true that by certain staining methods further identification within
these groups can be made. However, identification by microscopic methods
would still be very general, so that within each of these groups would be
hundreds of species which must be identified by other than microscopic
methods.

Both the tj'phoid and dysentery organisms belong to the third group;
that is, they are rod shaped. To the bacteriologist these forms are known
as "bacilli." Under the microscope, even with the use of stains, it is im-
possible to distinguish between them. Further, there are normally present
in water many other rod-shaped bacteria which are similar in appearance
to the typhoid and dysentery bacilli, but which are harmless. Therefore,
a direct microscopic examination of a water would supply little if any
information regarding its purity.

The major methods used in identifying and classifying all bacteria are
of a chemical and physical nature. They can be very simply explained
as follows. Bacteria, like plants and animals, are living organisms. The
main difference between the bacteria and higher forms of life is that the
former are single-celled while the latter are multicelled. Being alive,
bacteria must "breathe," they must "eat," and they must discharge the
by-products of that "breathing" and "eating"; even as all animals do. By
cultivating the organisms in known kinds of atmospheres, and by "feed-
ing" them known kinds and amounts of food, then analyzing the by-
products both chemically and physically, it is possible to identify and
classify them. Another factor that assists is the source of the organism.
Many species of bacteria, like many plants and animals, live and multiply
best in certain localities. With bacteria it may be the oral cavity, the in-
testines, or the skin uf man or animal; with plants and animals it may be
geographic locations.

It is by these methods then, rather than by the microscope, that the
bacteriologist determines the purity of a water supply. It will be noted
that the term used was "determines the pttrity of a water supply," not



PRIVATE WATER SUPPLIES 7

"determines whether or not the water contains typhoid or dysentery bac-
teria." For, and again some readers will be disappointed, even with these
chemical methods, no attempt is made to isolate disease-producing bac-
teria from the water. In other words, in the bacteriological test of water
no attempt is made by any method to determine whether ot not the water under
test contains typhoid or dysentery bacilli. The reasons for this are easily
understood.

As explained above, the microscope is of little practical value in de-
termining tlie purity of water. To date bacteriologists have been unable to
devise a direct method that is both economically and technically satis-
factory for the isolation of disease-producing bacteria from water. As
stated above, there are normally present in water many other rod-shaped
bacteria which are harmless in so far as disease-producing capacities are
concerned, but which so closely resemble the typhoid bacilli in microscopic
appearance and in their "breathing" and "eating" habits that it is possible
to distinguish ainong them only by highly specialized methods. In a
routine water analysis such highly specialized methods are not desirable
froin an economic standpoint, if for no other reason. The disease-produc-
ing bacteria are for the most part rather "fussy" in their habits. The harm-
less bacteria on the other hand are more rugged, more vigorous, than the
disease-producers. One might say that these latter organisms are the
"aristocrats" of the bacterial world while the harmless ones are the
"peasants" or "workers." When mixed together the harmless bacteria
will outgrow and outlive the disease-producers. This is particularly true
in a medium such as water, where the food supply is generally very
limited. This is another reason why it is so difficult to isolate typhoid



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