~ BALTIMORE CITY COLLEGE LIBRARY. ===>” Glass557.752 Book Accession | 09/2 af : — & : 7 f r 8 : ic@) a * « 7 - - - ie dy i “ih ; : Me aii eae ay iy ay Ms a rl iv oi Meta MARYLAND GEOLOGICAL SURVEY SUA Y se COUNTY at i ane | MARYLAND Ce Oro Gh SURVEY Si. (MARY'S COUNTY BALTIMORE THE JOHNS HOPKINS PRESS 1907 The Lord Baltimore Press BALTIMORE, MD., U. 8. A. MPLIMENTS OF _ : | WM. BULLOCK CLARK, Jouns Hopkins UNIVERSITY, ~ BALTIMORE, MD. Pe = , a —— == as = ——_ | 10912 COMMISSION EDWIN WARFIELD, : s : ; : : PRESIDENT. GOVERNOR OF MARYLAND. GORDON T. ATKINSON, COMPTROLLER OF MARYLAND. IRA REMSEN, : : ; : ; : EXECUTIVE OFFICER. PRESIDENT OF THE JOHNS HOPKINS UNIVERSITY. R. W. SILVESTER, . : : : : : ; SECRETARY. PRESIDENT OF THE MARYLAND AGRICULTURAL COLLEGE. SCIENTIFIC STAFF Wm. Buttock CiarK, . ; : : : . STATE GEOLOGIST. SUPERINTENDENT OF THE SURVEY. Epwarp B. MatuHeEws, : 5 . AssISTANT STATE GEOLOGIST. GrorcE B. SHATTUCK, . : : : : : : GEOLOGIST. B. L. MILuer, : F ; : : ; : : GEOLOGIST. C. K. Swartz, 2 F ; ; ; 3 5 : GEOLOGIST. E. W. Berry, ; F : ‘ j ; : : GEOLOGIST. A. BIBBINS, . . : : ‘ : : : : GEOLOGIST. Also with the codperation of several members of the scientific bureaus of the National Government. 7 it 7 Ww ca) 7 7 7 ell ne de ) At a) ay 7 _? : : 7 a a * ’ a ny + . a a) ‘ = x 7 Sth a ‘ : ; ni . UE a - = i y 7 ’ ae - es - 7 : a . : > | 7 ; : ; >i, a4 ke : ; o on) : ‘ : * ‘ ¥ a 7 a = ’ hase =i ra 7 | akan 7 axe o : 7 a oe . . a re ots au AN ggit ’ 7 r4 : pity : 7 2 rar, ote LETTER OF TRANSMIT VAL To His Excellency Epwin WanrFIELD, Governor of Maryland and President of the Geological Survey Commission. Sir:—I have the honor to present herewith a report on The Physical Features of St. Mary’s County. This volume is the fifth of a series of re- ports on the county resources, and is accompanied by large scale topo- graphical, geological, and agricultural soil maps. The information con- tained in this volume will prove of both economic and educational value to the residents of St. Mary’s County as well as to those who may desire information regarding this section of the State. I am, Very respectfully, Wm. Buttock CiarK, State Geologist. JoENS Hopkins UNIVERSITY, BALTIMorE, March, 1907. et barat ¥ tac iehy : Lanes aie, wa eG Fs. SO Peiy pa ee ad ay. 7) Ji 7 so « ~~ . anes Pa) a atl iy ay 7 fe Mia a3) eee es a oe Byala ee & IMO 1 Pate iy Fe op j ee. CONTENTS PAGE IPRUBIDYNGI caoanedeendanesoanopoan cpccDeoooUGogubn sUneUnTUCUDUOE OoOuO 17 IDSMPRAOADAUKCMENGIN) go sadtboconconvocgsucd copune oon DONOR OnOOUSUNUOB GUE 21 DEVELOPMENT OF KNOWLEDGE CONCERNING THE PHYSICAL FEATURES OF ST. MARY’S COUNTY, WITH BIBLIOG- RAPHY. By Grorcr BURBANK SHATTUCK......-.....0.eecce. 25 EN TROD UT OUOR Yammctsrcrerettete ici tenc ver eusiete sce sseter eich eel crencvcuerereteyere/ailot lis selialls eee ee teuskie 25 PELE RONG Adie PURI VERS W ame Cr petetc¥ifosa)sistareiaierscepara/s/ctalasais.iclisiefeis laisis/al ste suandhevaya aye les efs0s 25 RHewEN Stony, OF GeOLTAphI CVRESCALCHN: eve ci crctere tetas lsuc civ’ eielleselersueveveisde cvereve’s 26 MhHepElistorynotaGeolosicy RESEATCH soc a acie cis «oie suscclarete ciate eur icles) are sions 3 ESEESENT ORL AED Ned eee vatleteyietcNer oh viata oc ok capmter eaten aya! aiaies cnet oes aie jsauatah al neibataiead sare schats 3 THE PHYSIOGRAPHY OF ST. MARY’S COUNTY. By Grorcre BURBANK SSCAUISIVUT Cioumraeyenatenatesatovenet one susie ie teyuewer clie Gollcheirelisy'sNevapatta ye! even ove se sive love faltcveyeriage 55 EN ROD UW. CLO BVM Mmce vey die one ee vos et ele tera hel eievaneie vale foi elise hey cieve ds acre. 0s craije renova cusp ore (evs) aySie 55 MOPOGRAP TT OPI HS CRIPTION PF Acts jarcvei = rots isa) syereieselers) custo c) 3) sve /Susveveserecsas svajler cis ecere lees 56 MhHenOrainarer onsen Maiiy Ss COUNTY. ce cre segue ena oe a ietere.s duaisiepel «: ciaiaenatayeuece 59 Mhessunucturesof they Coastal wPlain’, cere. oc) ciect cin aisus crejelemy nial eissenal eles 61 ROPOGRAPELICMELES TOR Yatra crecrcye veya saleca tale torsvor clsTelel eis, sisiaonescheret sei0) ossteve (eee cele 61 MHSMMALAV SLES SEALE tartare sretepe seks ctesits sjauciale craic cre sia sia eae aiieerenerstens 6L PRHeeStaAderlan diS taeeusnni.ictacisiscteus.creleyeislevsl sotts o alecs lerelaielave alaversuers aye-v/eue 62 MN OEAWHCOMICO) SCALE yaa elerst crave ores pelaraucrevoneseeny ofa asvs alters oa eave felons ie. elecevels 63 THER PAlDOERSTALE) ere-e roses wigjend che isola whelcavorsvecs ‘c-aie) where Grererolenetens ust: al tpn feleie:s@layele 'eo-o\sislinrei eller 144 THE CLIMATE OF ST. MARY’S COUNTY. By C. F. von HerRMANN.... 147 TORR DEMO Bai ecoyats hater sncteseysitiara.ain sata sons syopecelesens ce sucdetmistefesrebe oicyend is vace'oue niate 147 Crimatic DATA AVAILABLE FOR ST. MARY’S COUNTY..............+2000- 148 FREE MRE APE RA TURE CONDUCLONG ara ritiatalaue: snelicie ehelsfensie sveceisie)oiels wie\el(einseis, 2) 5s 151 ERNE al peATLOMAILCS maces seuss cicterce hehe late ceciiatee for owed Scovreregereiuiele lente eosie eaten 155 PCCD LALO Meee Pa ates oreseye een se cteastatete ay sacra totenentadiapereeonesepeesiee ies See sree see wceiauals 158 14 CONTENTS PAGE THE CLIMATOLOGY OF) CHARLO TPE SEDATE crstelaca pete lsrateleietspeiats sist terstencr stereo) telomere 161 INTRODUCTORY. ier cf aiaveh tccksvetorehetehe arenes oie cokodoateteneuet ett neneneE Rete ntazere nets oa-EesEsr evens 161 THE) TEMPERATURE) CONDITIONS ayejcretetrciet cisaleienstoenebersheral svereitei stein sncrepetesere 164 Duration: Of War mlsWaviesien crac sci encleriolerseleeitatcmteraber-esteysterei hetoecctsieyods 169 Duration OfaColdPPeriOds ereicts crerstenetevey oka cevel te enctietlencencttedatel ele eiateeehe te getetieral ane 170 Durationvol thet Cropy Season cis siepercrersicnessteyson tet cler stoned farsieisiet enone ons 172 PRECTPIDATION: treme eie severe serterensier steieislerlatenchoncistonatsistcbel teelseeusheresicietenene icy eleatate 173 SmOWLAallls wes Me Boe So eS rerancretetie Raa taeksveleiel ei aie douseencue sacueicvatose etateatrebere tobeye 175 SWALNIDS! AUN Dic WEA TET EIR fete yetavers res cterchele pel cislicitsnelte aiaienereite)« tereie ceetevs (one caterstatstansetanete 176 THE HYDROGRAPHY OF ST. MARY’S COUNTY. By N. C. Grover.... 177 Ghapticori Cree knees seo tre ckoraehenetatersns rete teueletscensvs tetots ois ieeekezeve teehee ete temeremete hd, Ste @lemrentvRiyeriere sterctatereavererce tert tere averay a taltcnstevelereyateversneiscncerenerkaieie tore 178 Wilby, ehh “oman dn ovo booadoabolouor ooucoddcooccdaroonToGdso0dn 178 THE MAGNETIC DECLINATION IN ST. MARY’S COUNTY. By L. A. 18 y-(0) 1: Pee Hist Oe ORO tin Den OE OLIG DO tonG Onc aMD ooo td US O10 179 DESCRIPTIONMO Rs S TATIONS) eremreeeieric sn cratielkel mieislensieiclorole cieieiate tier tetera 179 IMBRID GAN pp LALINIEN® tailotn 199 FUTURE OF THE FOREST UNDER JUDICIOUS MANAGEMENT........-+---+-+- 200 GQUMEMARY: Gocclty ere rove a Diets Mate cele lolol tee oees totekenoratersWayelinreysncpotet ne) sieliegstaletstalts 203 TINUE 2 eee ices fe sie eats rie sees encbe te ey eke suena hope ey yee erase Pasatoueehelo/eceolaletetictsremeteha 205 PLATE VI. VII. VIII. IX. XVI. ILLUSTRATIONS FACING PAGE Fig. 1—View showing topography at Leonardtown............. Fig. 2.—View looking up the Patuxent River showing Drum Cliff Hiesee——Auneaner view Of MxM CUTE sy. cyercre iw «\. a} a io fe at vi - as 7 4 | sa ; a 7 - : ma | 7 7 on ed . fl i Lae i MARYLAND GEOLOGICAL SURVEY 101 various terraces of the Columbia group, the analogy is found to be so striking that the conclusion regarding a common origin of both is irre- sistible, and there can be no reasonable doubt that the mode of formation of the modern terrace furnishes the key to the interpretation of the ancient. The subsidence of the Atlantic Coastal Plain, which carried down beneath the ocean level the entire surface of St. Mary’s County, gave opportunity for the waves to finish the destruction of such portions of the Lafayette formation as chanced to survive the erosive work of the _ streams. As St. Mary’s County sank slowly beneath the water, the shore of the advancing Atlantic gradually worked further and further landward until it finally came to rest near Charlotte Hall. St. Mary’s County at that time was being rapidly covered by an off-shore deposit of mud, sand and gravel. How long the sea remained in this position is not definitely known, but it is certain that it remained long enough for the waves of the Sunderland sea to cut a well pronounced scarp-line against the Lafayette. These ancient sea cliffs are to-day prominent features of the topography of southern Maryland and may be mapped as easily as the sea cliff which is now being cut by the waves of Chesapeake Bay and its estuaries. While the Sunderland off-shore deposits were still in process of forma- tion over the surface of St. Mary’s County, the region rose again above the surface of the water and erosion began vigorously to cut away the loose sands and gravels which had been deposited just before. How extensive this uplift was, it is now quite impossible to say. It is equally difficult to determine its duration, but it was of sufficient length to permit the destruction of a large portion of this Sunderland formation, for many of the larger streams within St. Mary’s County opened up deep valleys within it. The question as to whether the Patuxent River first came into exist- ence at this point or previously in the erosive interval which followed the uplift of the Lafayete formation has been discussed elsewhere in this yolume. After St. Mary’s County had been subjected to erosion for a certain 102 THE GEOLOGY OF ST. MARY’S COUNTY period, it was again submerged, but not to the same extent as in the previous cycle, during the deposition of the Sunderland formation. The subsidence, however, was sufficient to drown the rivers which had opened up their valleys across the county and to transform these into estuaries, so that a waterway extended across Calvert County from what is now the mouth of Fishing Creek to the mouth of Hunting Creck. Another waterway from the south ran from Drum Point south- westward to what is now the head of the Hunting Creek estuary, and a third extended from what is now the mouth of Parker Creek across the divide to Battle Creek. Other streams of less importance were also trans- formed into estuaries, so that the county presented a most irregular shore line and the lower half of the region was transformed into a group of small irregular islands. The subsidence at this time amounted to about 90 feet. As the region remained at this level for some little time, the waves along the shore had an opportunity to do considerable erosive work and forced the shore lines back toward the rivers, widening the valleys which had been previously opened during the erosive interval which followed the uplift of the Sunderland formation. The material which was derived from the wave erosion was deposited along the floor of these estuaries, filling them in to a considerable extent and raising them up to a higher level than that which they possessed when the country was submerged at the beginning of the epoch. While this pro- cess of sedimentation was still in progress, the country once more rose above the level of the waves and permitted the streams to cut again in their old valleys. This epoch of elevation was apparently a short one for there was not enough time to enable the streams to completely re- establish themselves throughout the entire length of their former valleys. They had only partially begun the erosive work when the country was once more submerged beneath the waves and the deposition of the Talbot terrace was begun. At this time, the streams were once more transformed into estuaries, but not to the extent which they were in the previous Wicomico cycle of deposition. The land did not sink more than 45 feet below its present altitude and remained there for only a short time when it was once more raised and eroded. This epoch of elevation was the one MARYLAND GEOLOGICAL SURVEY 103 which ushered in the present cycle of events and permitted the cutting of the Recent sea-cliff. Since its initiation, the land has once more as- sumed a downward motion, and the entire coast line in this region seems to be sinking once more beneath the level of the waves. Along the shore of Chesapeake Bay and the lower courses of many of its estuaries there occur at intervals deposits of greenish-blue clay developed as lenses in the body of the Talbot formation. Usually the base of the clay is not visible but its stratigraphic relations are such as to leave no doubt that it, or a thin gravel bed on which it occasionally rests, is uncomformable on whatever lies beneath. The upper surface of these clay lenses is everywhere abruptly terminated by a bed of coarse sand or gravel which grades upwards into loam and at its contact with the clay strongly suggests an unconformity. These clay lenses are in some localities devoid, of fossils but in others they contain remains of marine and estuarine animals and land plants.. Many localities for these clays are already known and as exploration advances new ones are fre- quently discovered. Some of the more typical exposures will now be described. Along the shore, about a mile below Bodkin Point, Anne Arundel County, the variegated clays of the Raritan formation are finely exposed in a cliff some 30 feet in height. These clays occupy the greater portion of the section and carry an abundance of lignite more or less incrusted with crystals of pyrite. Sands and gravels of the Talbot formation un- conformably overlie the clays and constitute the upper portion of the cliff. Half a mile farther south the cliff still maintains its former height, but the section has changed. Some ancient stream must have established its valley on the Raritan, for here the surface of that formation, like a great concave depression, passes gradually beneath the beach to appear again in the cliff 150 yards to the south. In this hollow, lying unconformably on the Raritan formation, is a bed of dark-colored clay about 15 feet thick. Bluish and greenish tinted bands of clay relieve somewhat its somber aspect, and at about its middle portion it carries a bed of peat. But its most striking feature is the presence of huge fossil cypress knees and stumps which are imbedded in its lower portion. These stumps 104 THE GEOLOGY OF ST. MARY’S COUNTY vary in diameter from 2 to over 10 feet, and after the removal of the surrounding clay, stand out prominently in the position in which they must have grown. Mr. A. Bibbins, to whom the author is indebted for notes on these deposits, has counted 32 of these stumps which were visible at one time, and also reports finding worm-eaten beechnuts inti- mately associated with cypress cones near the base of the formation. Sands and gravels of the Talbot formation overlie the whole. Imme- diately south of this outcrop the dark-colored clays are temporarily re- placed by the Raritan formation, but they appear again a little farther down the shore, and afford an almost unbroken exposure for about a mile. The thickness of the clay in this locality is at first about 10 or 12 feet, but it gradually becomes thinner southward and finally disappears alto- gether. Casts of Unio shells and not vegetable remains, are its pre- dominant fossils, while, like the beds containing the cypress swamp, it overlies the Raritan formation unconformably, and is itself abruptly buried beneath Talbot sands and gravel. Another locality is on the Bay shore, about a mile northeast of Drum Point. Here, at the base of a cliff about 30 feet high, is a 2-foot bed of dark, chocolate-colored clay carrying gnarled and twisted sticks pro- truding in every direction from the material in which they are imbedded. Above this occurs a thin seam of lignite 14 feet thick, which in turn is overlain with about 5 feet of slate-colored clay. At this point the con- tinuity of the deposit is interrupted by a series of sands, clays, and gravels belonging to the Talbot formation, which extend upward to the top of the cliff. Although the base of this lignitic clay series is buried beneath beach sands, field relations lead to the conclusion that the de- posit is very much younger than the Miocene clays on which it rests un- conformably. A similar section is to be seen on the Patuxent River, about a mile below Sollers Landing. Large stumps here protrude from a dark, basal clay bed, some 5 feet in thickness, which is covered by 3 feet of sand, and this again is buried beneath 10 feet of Talbot sand and gravel. The relations of the basal clay to the underlying Miocene is again obscure, but indications point to an unconformity. Another section is exposed along the shore 14 miles northwest of Cedar Point, MARYLAND GEOLOGICAL SURVEY. ST. MARY’S COUNTY, PLATE X. Ci CHARACTERISTIC FOSSILS OF THE PLEISTOCENE OF ST. MARY'S COUNTY. 1. ILYANASSA OBSOLETA (Say) Dall. 9. Rancta cuneata (Gray) Dall. 2. EupLeura caupata (Say) Holmes. 10, Arca (NoETIA) PONDEROSA Say. 3. Porynices (NEvVERITA) DuPLIcATUS (Say) Dall. tt. Mya ARENARIA Linné. 4. FULGUR CANALICULATUM (Linné). 12. BARNEA (ScoBinA) costata (Linné) Dall. 5. Hrcorra GLABra (Mill) Britton. 13. OSTREA VIRGINICA Gmelin. 6, 7. CoRBULA CONTRACTA Say. 14. TootH oF Mastopon, MAMMUT AMERICANUM 8. TAGELuS Gippus (Spengler) Dall. (Kerr) (greatly reduced). io im Po ene. rh Pe ee en a oN Bik Sl es. ei 1% rr ane x a a 4 2 ns i _ “un 1 * Ea Sin ao Aff cae h9 : hits Sle ames i ead | Hy ee ee epg oe ‘1 See VL So es 7 eae eee ec ek ee eee | a cae ; r >> oo Aaa oT : 7 } fue, ae Wc . Daa © ae i 7 7? ae 7 fi 7 a i oe ar ie i _ sary Sy Nee i a ex 7 r a rp : ri Pye Me ea MARYLAND GEOLOGICAL SURVEY 105 where a thin bed of drab clay carrying vegetable remains is overlain abruptly with sands and gravels. Its contact with the Miocene is again unfortunately obscure. At the localities just described no animal re- mains have been discovered, but on the north bank of the Potomac, about half way between St. Mary’s River and Breton Bay, there is a deposit of lead-colored clay, exposed for a quarter of a mile along the shore. It is buried at each end as well as above by sands and gravels and carries hoth lignite and Rangia cuneata (Conrad). Although the description given by Conrad is somewhat vague, it is highly probable that he visited this locality and collected specimens of the fossils. Two more localities still remain to be mentioned, Cornfield Harbor, and its companion de- posit exposed 54 miles south of Cedar Point on the Bay shore. Conrad was well acquainted with these deposits and to the former he devoted special attention. Each is about 10 feet thick, occurs at the base of a low cliff, is composed mostly of a dark, lead-colored clay, and is overlain abruptly with Talbot sand and gravel, while unconformity on the Miocene is beautifully shown at the base of the Bay shore section. A number of fossils have been described from the Cornfield Harbor locality, among which are Ostrea virginica Gmelin, Arca ponderosa Say, Arca transversa Say, Venus mercenaria Linné, Mya arenaria Linné, Barnea costata (Linné), Crepidula plana Say, Polynices duplicatus (Say), and Fulgur carica (Gmelin). In this exposure the lower 4 feet of clay carries the marine forms and above this there are 2 feet of sandy clay literally packed with Ostrea virginica. These same general relations hold for the similar deposits south of Cedar Point. The stratigraphic relation of these lenses of clay which are surely unconformable on the underlying formation and apparently so with the overlying sand and loams of the Talbot formation is a problem which engaged the attention of the author until it appeared that the apparent unconformity with the Talbot, although in a sense real, does not, how- ever, represent an appreciable lapse of time and that therefore the clay lenses are actually a part of that formation. In order to understand more clearly what is believed to have taken place, these clay deposits should be divided into two groups, those which carry plant remains con- 8 106 THE GEOLOGY OF ST. MARY’S COUNTY stituting one, and those containing marine and brackish-water fossils the other. Such as are devoid of fossils may belong to either one of the groups according to their situation but probably more frequently belong to the latter. In a word, the clays carrying plant remains are regarded as lagoon deposits made in ponded stream-channels and gradually buried beneath the advancing beach of the Talbot sea. The clays carrying marine and Fic. 5.—Diagram showing pre-Talbot valley. brackish-water organisms are believed to have been at first off-shore deposits made in moderately deep water and later brackish-water de- posits made behind a barrier-beach and gradually buried by the advance of that beach toward the land. Taking up the first class of deposits in more detail they are believed to have been formed in the following manner : During the erosion interval which immediately preceded the deposition of the Talbot formation many streams cut moderately deep channels in the land surface, which on the sinking of the region again were trans- MARYLAND GEOLOGICAL SURVEY 107 formed into estuaries (Fig. 5). Across the mouths of the smaller of these drowned valleys the shore currents of the Talbot sea rapidly built bars and beaches which ponded the waters behind them and transformed them from brackish-water estuaries to fresh-water lagoons. These la- goons, however, were gradually changed into marshes and possibly to meadows by the inflow of detritus from the surrounding region and on the new land surface thus formed various kinds of vegetation took up Fic. 6—Diagram showing advancing Talbot shore-line and ponded stream. their abode (Fig. 6). At first the beach-sands advanced in the lagoon and filled up completely that portion of the submerged trough which lay immediately beneath them, but later, as the lagoon was silted up more and more with mud derived from the surrounding basin, the ad- vancing beach came to rest on this lagoon deposit as a foundation and arrived at length at the point where the lagoon had been filled up to the level of wave-base or higher. When this place was reached another process was added to that of beach advance. Heretofore the waves and wind had been simply pushing forward material over the advancing front 108 THE GEOLOGY OF ST. MARY’S COUNTY but now the mud deposit in the lagoon had actually reached the level of wave-work and had transformed the lagoon from a pond to a marsh or to a meadow, the breakers attacked the upper portion of the lagoon deposit and eroded it down to the level of wave-base as rapidly as they could reach it from under the superficial veneer of the beach-sands. Cypress, cat-tails, sedges, and other vegetation which had taken up their abode in the marsh would be overwhelmed with detritus by the advancing beagh _ Fic. 7.—Diagram showing later stage in advance of Talbot shore-line. and a little later be destroyed by the breakers. In this way all traces of life must be removed from the deposit except such as happened to occupy a position lower than wave-base. One, therefore, finds preserved in the clay water-logged trunks and leaves, nuts, etc., and roots of huge trees like the cypress. The area over which the waves had removed the upper portions of the lagoon deposit can be determined not only by the presence of truncated stumps but also by the character of the contact. Here there is a sharp division between the clay and the overlying sand and gravel while the area over which the beach advanced without cutting MARYLAND GEOLOGICAL SURVEY. ST. MARY’S COUNTY, PLATE XI. Fic. I.—VIEW SHOWING SWAMP LAND NEAR UNCLE. Fic. 2.—VIEW SHOWING BARRIER BEACH NEAR MILLSTONE. Rae seo e hae Gers ena é 7 7 Hi} ee ee i,” mee +4 os ee e Ted aw in Pay 8 oat Tog Ra ive! —% x ae MARYLAND GEOLOGICAL SURVEY 109 would be indicated by a partial mingling of the beach material with lagoon mud. A still later stage in the process is illustrated in the accompanying diagram (Fig. 7) which represents a stage where the waves have so far advanced as to largely destroy the original stream channel. A small portion of the old lagoon still exists at the head of the swamp but its lower portions have long since been submerged and covered over by the advancing beach. The transverse section shows what is left of the lagoon deposits of mud carrying truncated stumps of cypress and other trees which happened to be buried deep enough to escape the destructive powers of the breakers. The broken line indicates the outline of the clay lens. Fig. 8 is a section through the same region made at right angles Fic. 8.—Ideal section showing advance of Talbot shore-line. to the one just described. At D the breakers are forcing forward the beach upon the meadow. Just off from the beach the waves have swept away the sand and are eroding on the lagoon mud which reached out to them under the beach veneer. At C' the waves have succeeded in cutting down the lagoon deposit to wave-base and have left behind a thin veneer of sand and gravel as the sinking land carries it below the reach of the waves. At B the lagoon deposit was not thick enough to reach the zone of wave-erosion and simply grades up into a thick deposit of sand and loam which passes out toward A. The second category of clay lenses, namely those carrying marine and brackish-water organisms are understood to have been formed in a somewhat different manner. The lower portion. carrying the marine organisms points to salt-water conditions and contains remains of sea animals which live to-day along the Atlantic coast. At the time when 110 THE GEOLOGY OF ST. MARY’S COUNTY this deposit was formed, the ocean waters had free access to the region and the blue mud in which they are now imbedded and in which they lived was a quiet-water deposit laid down some distance from the land Later, however, it would appear that a barrier beach was constructed shutting off a portion of the sea-bed which had formerly been occupied by marine animals and gradually allowing it to be transformed from salt-water conditions to those of brackish water. In this brackish-water lagoon the fauna changed to that found along our estuaries to-day and huge oysters flourished and left behind them a deposit of shell-rock. With the bar advancing landward this lagoon was gradually filled up with sand and gravel and finally obliterated. The upper unconformity, then, in the case of the fresh-water and the brackish-water lagoons is real only in the sense that an unconformity in a cross-bedded wave- and delta-deposit is real. There is, it is true, a lack of harmony in the position of the beds and a sharp break is indicated but there is no indication of an appreciable time-lapse between the clay and the oyster-bed on the one hand and the overlying sands and gravel on the other, and the sea which eroded the clay to a fixed level immediately afterwards overspread the surface of the same with a vencer of beach sand. There is, therefore, no time break indicated by this unconformity and the lenses of swamp-clay as well as those carrying marine and brackish-water organisms are to be looked upon not as records of elevation and subaerial erosion but as entombed lagoon- deposits made in an advancing sea and contemporaneous with the other portions of the formation in whose body they are found. The hypothesis here advanced is based on and reinforced by many observations along the present shores of the Atlantic Ocean, Chesapeake Bay, and its estuaries. Each step in the process described above is there illustrated and some of them are met with again and again. As one passes along the shores of Chesapeake Bay and of the rivers which flow into it, stream channels are continually met which have arrived at more or less advanced stages in the above-mentioned process. Some are in part converted into lagoons, by bars built across their mouths, others show partial filling by mud washed in from the surrounding country, MARYLAND GEOLOGICAL SURVEY itis and still others have reached the advanced stage of swamps or meadows in which various types of vegetation are flourishing. In addition to the usual undergrowth which is found in wet places, the cypress has taken up its abode in these bogs and has converted some of them into cypress swamps. For great stretches along the shore the advance of the sea is indicated by well-washed cliffs while in other places the waves are found devouring beds of clay which are situated immediately in front of lagoon swamps and separated therefrom by nothing but a low superficial beach. These clay beds invariably he at and below water-level, are very young in age, and evidently pass directly under the beach to connect with the lagoon-clay beyond. This interpretation is made the more certain by the presence of roots in the wave-swept clays which but a short time before belonged to living plants identical with those now flourishing behind the beach, and point to a time not far distant when they also were a part of the lagoon swamp behind a beach situated a little farther seaward. At Chesapeake Beach a ditch has been cut through one of these beaches which shows a continuous deposit of clay from a lagoon swamp passing out under the beach to the Bay beyond. The waves are thus caught, as it were, in the act of eroding the upper portion of the lagoon deposit. From a large body of data gained from over a wide area, it is evident that the erosion which occurred during the interval between the eleva- tion of the Talbot terrace and the present subsidence of the coast was sufficient to permit streams to cut moderately deep valleys in the former. It would then appear that as the region was gradually lowered again beneath the present ocean the upper portions of the stream-channel in time passed below wave-base and whatever has collected in them since that period will be preserved beneath the advancing sea as a more or less fossiliferous clay lens apparently unconformable beneath beach debris. The barrier beaches which exist at intervals along the Atlantic coast of New Jersey, Delaware, Maryland, Virginia, and southward show us how portions of the ocean-bed, which were formerly bathed by salt water and sustained a marine fauna, are now converted to lagoons behind 112 THE GEOLOGY OF ST. MARY'S COUNTY barrier beaches, and have passed over in varying degrees to brackish- water conditions bearing estuarine faunas. Similar deposits to those just described have been seen by the author along the Rappahannock River, especially at Mosquito Point, and there is no reason to doubt that they occur in many other places along Chesa- peake Bay and its estuaries, within the State of Virginia. From analogy, it would be expected that similar deposits would be discovered along Delaware Bay where conditions must have been identical with those which prevailed in Chesapeake Bay. That such deposits do occur along the shores of the Delaware there can be no doubt. The most noted of these is at Fish House on the New Jersey side of the Delaware River a few miles above Philadelphia. MARYLAND GEOLOGICAL SURVEY. ST. MARY'S COUNTY, PLATE XII. Fic. I.—VIEW OF ST. JEROME CREEK SHOWING DROWNED VALLEYS NEAR RIDGE. Fic. 2.—VIEW OF BRETON BAY FROM ABELLS WHARF. _ 7 i i vi aie -_ sai : ae on > ua’ Sent eT) ee See se ) cena t ae ea a» i te, “ or eek: ae S THE ECONOMIC RESOURCES OF ST. MARY'S COUNT Y¥ BY BENJAMIN L. MILLER INTRODUCTORY. The economic resources of St. Mary’s County are neither varied nor especially valuable yet several of them are worthy of more attention than they have thus far received. Aside from the soils, which are foremost in importance and value and which are discussed in a subsequent chapter, the county contains several deposits of considerable economic value, none of which are, at present, utilized to their fullest extent. These are the clays, sands, gravels, glauconitic and shell marls, and diatomaceous earth. In addition, valuable water resources contribute much to the mineral wealth of the region. Almost all of these products have an especial value to the residents of the county in that they either contain ingredients for soil enrichment or materials for the construction of good roads. Since agriculture is the chief occupation it is believed that the general recognition of the value of the natural products of the region will lead to their greater use. This would eventually enhance farm lands through increased soil fertility and easier land transportation. Tue Narurat Deposits. THE CLAYS. The clays constitute the most valuable economic deposits of the region. Every geologic formation represented in the county contains argillaceous strata, even though, in general, the deposits are composed principally of sand. The argillaceous beds are quite generally distributed throughout 114 THE ECONOMIC RESOURCES OF ST. MARY'S COUNTY the region and, in a few instances, have furnished materials for the manufacture of brick. They are not suitable for pottery or the finer grades of brick but make a fairly good variety of common red brick. Since the clay supplies are ample there seems to be no good reason why the county should not produce all the brick and tile of this character required for local uses. Should a ready market be found and better means of transportation obtained, brick for shipment might perhaps be produced at a profit. However, since other counties in the State more favorably situated with respect to markets and the main lines of railroads contain equally extensive clay deposits, sometimes of a better quality, it is not probable that St. Mary’s County will ever become an important clay center. It should, however, produce enough brick to supply the local demand. Should the experiments that are being tried elsewhere of using burned clay for road metal prove to be successful some of the clay of the county may be profitably used in this way. Since the sandy roads seriously interfere with the development of the region there will undoubtedly be an increased demand, sooner or later, for cheap road metal, and it is possible that the clay of this region may partially meet this demand. The clays occur in deposits of both Tertiary and Quaternary age. TeRTIARY CxLAays.—Although argillaceous beds occur very frequently in the Miocene and Lafayette strata of the State, in general they are too sandy to be of much economic importance. The Calvert, Choptank, and St. Mary’s formations of the Miocene all contain beds of sandy clay which are well exposed in many places along the Patuxent River and in the other stream valleys. The Calvert, which outcrops in the northwestern portion of the county, contains more of this clay than do the other Miocene formations, and the clay is less sandy. It is bluish-green to black when fresh, but becomes lighter in color on exposure. It has never been worked and is probably of little economic value because of its large percentage of sand, iron, and lime. The lime is derived from the numerous fossil shells which are either generally distributed throughout the sandy clay or massed in definite shell beds within it. MARYLAND GEOLOGICAL SURVEY 115 The Lafayette formation, which is represented in this county by several small outliers in the vicinity of Charlotte Hall, usually contains a surface capping of clay loam which, elsewhere in the Coastal Plain, has been quite extensively used for brick. However, in this region, its small areal extent renders it of little value. QUATERNARY CLAys.—The clays of the post-Lafayette of the county greatly exceed in value those of the underlying deposits and are found in each of the three Pleistocene members. Their mode of occur- rence is very similar in the different formations as is also their general character. The clays occur in the form of a surface capping of clay loam representing the last stage of deposition in each epoch, and as lenses of light drab to dark brown clay contained in the body of the deposits. In all probability the surface loam was not everywhere developed and often where it was once present it has since been removed by erosion, so that it is by no means co-extensive with the various Pleistocene forma- tions of which it forms a part. It is extremely variable in thickness, ranging from a few inches to 6 or 8 feet in St. Mary’s County, while in other parts of the Coastal Plain it is often much thicker. The Sunderland formation contains a greater development of clay loam than it does in Calvert County, and for this reason the upland roads which are generally located on the Sunderland-covered divides are less sandy than in Calvert County. The clay loam of the Sunderland con- stitutes the greater portion of the Leonardtown and Norfolk loams, whose distribution is shown on the soil map of the county. In many places the materials mapped as loam are entirely too sandy for the manufacture of brick, but in many other places in these areas clay suitable for common brick can be obtained. Where the clay can be used the cost of removal entails only a slight expense because of the small amount of stripping required. Similar clays, utilized in Virginia are obtained by merely removing the few inches of surface material which is filled with plant roots. Beside the surface clay loams, lenses of plastic drab clay are fre- quently found near the base of the Sunderland deposits. These can be seen outcropping in many places on the steeper slopes. In general, 116 THE ECONOMIC RESOURCES OF ST. MARY'S COUNTY these lenses are of small extent but some are sufficiently thick and extensive to be worked, although in places they contain considerable vegetable material which renders them less serviceable. The clays of the Wicomico formation closely resemble those of the Sunderland both in general character and mode of occurrence. The surface loams in many places are suitable for the manufacture of a fair quality of brick, although they have never been used for that purpose in the county. Elsewhere in the State and in adjoining States extensive brick plants obtain their material from the surface clay loam of the Wicomico formation. In a general way the areas of Sassafras loam shown on the soil map of the county approximately represent the development of the Wicomico surface loams. It must be borne in mind, however, that a soil map and a geological map are constructed on an entirely different basis and seldom do the lines defining the areas of certain soils coincide with the boundary lines of the geological formations. Some small portions of the Sassafras loam are of Sunderland age and some belong to the Miocene yet the greater part represents the Wicomico surface loam. Further small portions of the Wicomico surface loam are mapped as meadow soils on the soil map. ‘The clay lenses of the Wicomico which resemble those of the Sunderland are not extensive enough to be of any particular importance. The loam cap of the Talbot is more persistent than is that of the Wicomico and Sunderland formations, and is almost co-extensive with the distribution of the Talbot formation in this county. Just across the Patuxent River, in Calvert County, near Solomon’s Island, brick was formerly made from the Talbot clay loam. In St. Mary’s County these Talbot loam areas are most extensive along the Potomac River, where they cover the low, flat divides between the tributary streams. With the exception of the valleys of the smaller streams the meadow soil areas of the soil map approximately coincide with the distribution of the Talbot surface clay loam. As has been demonstrated by the brick plant in Calvert County, the Talbot loam produces a fair quality of brick. Beside the surface Joam of the Talbot, there are several other deposits MARYLAND GEOLOGICAL SURVEY Tally of clay present in this formation which doubtless have some value. They consist of lenses of bluish-green to black plastic clay which have been exposed through wave-cutting along the Bay and the Potomac River in the southern portion of the county. The best exposures of this material occur along the Bay shore about 5 miles south of Cedar Point, at Wailes Bluff, along the Potomac River, about 1 mile north of Cornfield Point, and on the east shore of Breton Bay, about one-fourth mile below Lovers Point. Similar clays occurring at Bodkin Point near the mouth of the Patapsco River have been tested and described by Dr. Heinrich Ries. He states that the clay “burned to a good red color under ordinary conditions and to a deep brown when vitrified. Before this clay could be used in large ware it would be necessary to add sand to prevent excessive shrinkage.” In certain outcrops these clays contain sufficient vegetable material to render them unfit for use but in others they contain very little organic matter. THE SANDS. Since the arenaceous phase predominates in almost every formation represented in the region, the county contains an unlimited supply of sand. The sand of the Pleistocene is used locally for building purposes, but since it is so readily obtained in all parts of the county no pits of any considerable size have been opened. It is said to be a fairly good building sand yet no better than quantities of sands in other parts of the State, hence the demand for it is purely local. In some places the quartz sands of the Miocene seem to be pure enough for glass-making, suggesting the Miocene glass sands so extensively ex- ploited in southern New Jersey, although they have never been used for that purpose in this region. Careful chemical analyses and physical tests, which have not been made, would be required to determine their usefulness in this respect. Locally, the Pleistocene sands are rich in ferruginous matter which, in places, cements the grains together forming a ferruginous sandstone. 1Md. Geol. Survey, vol. iv, 1902. 118 THE ECONOMIC RESOURCES OF ST. MARY'S COUNTY Sands of this character possess a distinct value for road-making pur- poses, as they pack readily and make a firm road bed. Where the material can be easily obtained in large quantities good roads of this kind can be very economically constructed. The ferruginous sands are best developed in the Sunderland formation, principally because of the ereater age of the deposits, although also represented in the Wicomico and the Talbot. THE GRAVELS. The Pleistocene formations contain numerous beds of gravel widely distributed throughout the region. They occur in pockets or lenses, either immediately at the surface or but thinly covered by the sands and loam. In the latter case they can be seen in many places outcropping along the valleys. These gravel deposits have only been used to a small extent in this section although similar deposits in the vicinity of Wash- ington have been extensively worked. As ballast for roads they possess considerable value and will doubtless be extensively used in the future in the building of permanent roads throughout the county. They are probably inferior in value to the igneous rocks yet serve their purpose well when properly used. They are generally rich in iron, which acts as a cementing agent, although there are many places where the gravels lack this desirable material. In such cases it is necessary to add ferru- ginous sand or clay to bind them together. The gravels range in size_ from coarse sand to pebbles several inches in diameter. They are especially well developed at the base of the Sunderland formation and are exposed in almost every place where streams have cut through the overlying loam and sand. Many of these outcrops of Sunderland gravels are represented in the soil map as the Susquehanna Grayel areas. THE BUILDING STONE. Although the formations of the county are composed almost entirely of unconsolidated materials, yet locally indurated beds are not uncom- mon. In the absence of any better stone these indurated ledges furnish considerable material for the construction of foundations and well walls. MARYLAND GEOLOGICAL SURVEY 1a) At Sotterly Wharf, on the Patuxent River, there is a firm ledge of Miocene rock which has been used for such purposes. Elsewhere ferru- ginous sandstones and conglomerates from the Pleistocene deposits supply the small local demand for rough building stones. THE MARLS. Extensive deposits of shell marl have a wide distribution throughout the Atlantic Coastal Plain and have been worked, at intervals, since the early part of the last century, when their value as fertilizers was first determined. However, their importance in the enrichment of soils de- ficient in lime has never been generally recognized. At present their use in Maryland has been almost entirely discontinued, although the deposits are practically inexhaustible. At the Nomini Cliffs, just across the Potomac River, in Virginia, shell marl has been dug for shipment and used in the manufacture of artificial fertilizers. The Calvert, Choptank, and St. Mary’s formations all contain beds of shell marl which are exposed in the river cliffs and valley slopes in many places throughout the county. The Talbot also contains deposits of shell marl at Langleys Bluff, on Chesapeake Bay, about 5 miles south of Cedar Point, and at Wailes Bluff, on the Potomac, about 1 mile above Cornfield Point. The shell beds of the Choptank are the most important and are particularly well exposed at Drum Cliff, on the Patuxent River. In places the shells are mixed with so much sand that the lime forms only a small percentage, but in other places the amount of lime exceeds 90 per cent. The value of the shell marls and methods for using them are thor- oughly discussed by Professor H. J. Patterson in a Bulletin of the Maryland Agricultural Experiment Station (No. 66, May, 1900). He states that the lime has an especially beneficial effect upon sandy soils, such as prevail throughout St. Mary’s County, in improving their physical characteristics. This it does through its cementing action which ren- ders such soils less porous and thus enables them to retain moisture better. Chemically, lime corrects the acidity of the soils through its neutralizing effect upon acids, acting upon other soil constituents, ren- 120 THE ECONOMIC RESOURCES OF ST. MARY'S COUNTY dering them available for plant food, and finally serves as a plant food itself. Many experiments which have been tried in various places all show the value of lime as a fertilizer, and experiments in this State show that better results were obtained by the use of shell marl than with burned-stone lime. No doubt, any of the soils of Calvert County might be considerably improved at small expense by the generous use of shell marl, deposits of which are readily accessible to a large part of the county. THE DIATOMACEOUS EARTH. Diatomaceous earth, infusorial earth, or tripoli is a siliceous deposit composed mainly of the microscopic tests of diatoms, a low order of aquatic plants. The material is scft, porous, light in weight, and very friable. When fresh it is greenish in color but on exposure to the air the color changes to buff or almost pure white. The diatomaceous earth occurs in the lower part of the Calvert formation and is well exposed in many places along the Bay and river shores and in the tributary stream valleys in the northwestern portion of the county. The diatomaceous earth, on account of its porosity and compactness, is used in water filters. It is reduced readily to a fine powder and makes an excellent base for polishing powders. On account of its porous nature, diatomaceous earth is used as an absorbent in the manufacture of dynamite, while its non-conductivity of heat makes it a valuable in- gredient in packing for steam boilers and pipes, and in safes. This latter is the principal use to which it is put. It has been thought that the diatomaceous earth might be of use in certain branches of pottery manufacture, which require on the part of the materials refractoriness and an absence of color when burned. Dr. Heinrich Ries tested a sample of the diatomaceous earth from Lyons Creek at cone 27 in the Deville furnace and found that the material fused to a drop of brownish glass. The non-refractory character of the diatomaceous earth is thus clearly demonstrated. It is also used in the manufacture of fire and heat- retarding cements and fire-proof building materials, such as solid brick and hollow brick for partition walls and floors. MARYLAND GEOLOGICAL SURVEY 121 Not all of the diatomaceous earth of the region is valuable, some con- taining an excessive amount of sand. At Lyons Creek wharf, in Calvert County, it is quite pure and has been worked for a number of years by the Maryland Silicate Company. Because of the limited demand for it and the considerable number of States in which diatomaceous earth is found it is improbable that the industry in southern Maryland will ever reach very large proportions. THE WaTER RESOURCES. The available water resources of St. Mary’s County include the surface streams, natural springs, and the dug or driven wells. In the absence of large towns or great industries where large amounts of water are re- quired, the streams have not been utilized for water-supply purposes. In fact, it is doubtful if they could ever be depended upon for potable water because of the large amount of vegetation which they contain during the summer months and the lability to contamination from the run off of the adjoining cultivated lands. In some instances dams have been constructed and the power utilized by small manufacturing con- cerns, but because of the gentle slope of all except the smallest streams the amount of water-power developed is very slight. Sprincs.—The nature of the topography of the region with many stream-valleys cut almost to sea level combined with the gentle dip of the different beds of varying permeability afford excellent conditions for the development of springs. The ground water sinking through the porous Pleistocene deposits until the less porous beds of the Miocene are en- countered, flows along the contact until it is tapped by some valley slope where it issues as a line of seepage or as a spring. A large per- centage of the ground water is not checked at the contact of the Pleisto- cene and Miocene but passes downward through the sandy layers of the latter formation until its further progress is checked by more argillaceous beds along which it flows until the layer outcrops at the surface. The more deep-seated springs of the latter sort which penetrate Miocene beds are apt to be purer than the shallow springs and furnish an unfailing supply of excellent water. In addition to the increased danger of con- 9 122 THE ECONOMIC RESOURCES OF ST. MARY'S COUNTY tamination in the shallower springs, they are very apt to fail in dry weather. Some of the springs are remarkable because of the large quantity of exceptionally pure water which issues from them, and also because of their continuous flow since the earliest settlement of the State with probably undiminished volume. The most famous one is Governor’s Spring, a short distance east of St. Mary’s City, which was the first permanent settlement in Maryland and for a long time its capital. Another spring, equally well known, is the excellent spring at Charlotte Hall which has long furnished the supply of water for the boy’s school at that place. While the spring-water is sometimes slightly charged with iron derived, in the main, from the Pleistocene deposits, it is, as a rule, remarkably free from mineral matter of any kind. Exceptions are the Diuretic Mineral Spring of Blakistone Island, from which water has been sold, and the chalybeate springs at Rock Springs, a few miles northwest of Blakistone Island. Duce Wetis.—Except on the top of narrow divides between deep valleys, the ground water level hes near the surface and abundance of water can be obtained from dug wells of shallow depth. On the narrow divides, however, the water table in the dry months of the year hes only a little above sea level, thus necessitating the sinking of wells almost to that plane in order to obtain a permanent supply of water. The highest divides in the county rise to an elevation of about 180 feet and in a few instances it has been necessary to sink wells to almost that depth to secure plenty of water during all seasons of the year. On the broad, low-lying flats bordering the Potomac River, on the other hand, it is seldom that the wells exceed 20 feet in depth and sometimes the water rises to the surface. In general the water in these most shallow wells is much more apt to be impure, although in many places it is used exclusively without any apparent injurious effects. ARTESIAN WELLS.—As good water in sufficient quantity can be ob- tained almost everywhere in the county at moderate depths few attempts have been made to obtain artesian water, except in the low-lying regions MARYLAND GEOLOGICAL SURVEY 123 adjoining the Potomac and Patuxent rivers, where flowing wells can be secured at moderate expense. Also in those localities the water in the shallow wells is sometimes brackish and at times become stagnant and unfit for drinking purposes. Few flowing wells are known within the county with sufficient artesian pressure to force the water more than a few feet above tide. The well at Chaptico, which rises 22 feet above tide, is exceptional. The water obtained in the artesian wells usually contains some mineral matter in solution but not sufficient to interfere with its use for most purposes. When the wells are protected from surface contamination, the artesian water is the most healthful water obtainable in the county. There seems to be three distinct water horizons that furnish the supply for artesian wells thus far sunk. One of these occurs in the deposits of the Aquia formation, one of the members of the Eocene, which probably underlies the entire county but nowhere appears at the surface in this region. ‘To the northwest of St. Mary’s County, in Charles County, it rises to the surface and outcrops along many of the streams. The other horizons occur in the Miocene strata, one near the base of the Calvert formation and the other probably in the Choptank formation. The Hocene horizon.—This horizon supplies several artesian wells along the Potomac River in the western part of the county. A well at Chaptico from which the water flows to a height of 22 feet above tide penetrates this horizon at a depth of 291 feet. Another well, 275 feet deep, 2 miles west of Maddox, obtains its water from the Eocene, perhaps from strata somewhat higher than the water-bearing beds in the Chaptico well. Other wells supplied with water from the Hocene horizon include several wells at Oakley about 305 feet in depth, and one at Bushwood 287 feet deep. This horizon undoubtedly extends to the eastward, but since east of Oakley artesian water is obtainable from Miocene strata at shallower depths borings have not been extended to the Eocene horizon. The Miocene horizons—The principal water-bearing horizon for the greater part of the county lies near the base of the Calvert formation. Many wells have been sunk to this horizon and a good supply of water 124 THE ECONOMIC RESOURCES OF ST. MARY'S COUNTY has almost invariably been obtained. On the Patuxent River side of the county good flows of water are obtained from a 225-foot well near Sotterly wharf, from two wells 290 feet in depth at Millstone, and from two wells 257 and 287 feet deep east of Pearson post office. In some cases the wells have been sunk beneath the water-bearing horizon, thus making the horizon, from the depths of the wells, appear to be very uneven. In reality it seems to dip at a quite uniform rate to the south- east, and consequently the wells in the lower portion of the county are deeper than those higher up the rivers. Along the Potomac River the Calvert horizon furnishes the water for the 190- and 205-foot wells at Leonardtown, a 270-foot well at Piney Point, numerous wells about 270 feet in depth on St. George’s Island, several wells near St. Inigoes from 300 to 365 feet deep, a well on the west bank of Smith Creek 365 feet in depth, and two wells near Corn- field Harbor 360 and 370 feet deep. One other water-bearing horizon has been found at Cornfield Harbor at the depth of 240 feet. This is probably within the Choptank forma- tion. It is probably less extensive than the basal Calvert horizon, since it has not been noticed elsewhere. The two principal water horizons described above have been penetrated by wells on the opposite side of the Patuxent River in Calvert County, and on the south side of the Potomac River in Virginia. ipiesS OLS O Sie MARYS, COUNTY BY JAY A. BONSTEEL INTRODUCTORY. St. Mary’s County comprises about 369 square miles of territory, bounded on the northeast by the Patuxent River, on the east by Chesa- peake Bay, on the south and southwest by the Potomac River, and on the west by Wicomico River and Budds Creek. All of these waters except Budds Creek are either salt or brackish, and in the Patuxent and Potomac rivers the tides rise to points far beyond the boundaries of the county. On the north, for a distance of about 25 miles, the boundary separating St. Mary’s from Charles County is an irregular land line, except along the northeastern portion, where Indian Creek forms the boundary. The county is irregular in outline, constituting a large peninsula stretching southeastward and is the most southern of the Maryland counties occupying the western shore of Chesapeake Bay. St. Mary’s County lies wholly within the Coastal Plain area of Mary- land. It consists of an interior upland division, rising from 90 to 200 feet above sea level, and of a low-lying foreland border varying from 15 to 45 feet above sea level. The county is very much indented by large estuaries or bays, particularly on the Potomac side. The streams of any length flow into the Potomac drainage system, while only steep- walled streams of short length are tributary to the Patuxent. As in Calvert County, the basal skeleton of St. Mary’s County consists of unconsolidated strata. The materials composing these strata are the same as in Calvert County. In the same way the later Pleistocene de- posits are far more directly concerned in the formation of soil types than are the older strata, and the correlation of soil types with geological 126 THE SOILS OF ST. MARY’S COUNTY formations given in considerable detail for Calvert County also applies to St. Mary’s. The chief geological difference between the two counties lies in the fact that in St. Mary’s the Eocene strata do not reach the surface, while in Calvert they do, and the St. Mary’s formation is much more widely developed in southern St. Mary’s than in Calvert. THE Sort Types. The soils have approximately the following areas: AREAS OF THE DIFFERENT SOILS. | Soils. Acres. | Per ct. Soils. Acres. | Per ct. Leonardtown loam ........ 95,500 41 | Norfolk loam............+- 8,500 4 MGAGOW cress cicencvecel cence 54,200 23 | Susquehanna gravel...... 7,350 3 INONLOIKISANG Fa smiceicisentcitices 27,500 12 | Windsor sande 5 ssccie es 3,450 2 Sassafras sandy loam...... | 17,500 AMS NVATN Ds istees cleteisreryericneteeies 2,200 1 Sassafras loam............. | 16,200 7 || The Norfolk Loam. Norfolk loam extends as a long narrow strip along the highest portion of the divide between the Patuxent River drainage and that of the Poto- mac River. It also occupies small, irregular, scattered areas covering the fiat plateau of the northern portion of the county. Along the Three Notch Road, which follows the main divide of the county, the area occupied by the Norfolk loam presents a slightly rolling upland, varying from 120 to 165 feet in elevation. The highest eleva- tions and the intervening hollows are included in the area covered by this soil. The soil itself consists of a fine sandy to silty loam, reaching to an average depth of about 1 foot. When dry it is powdery and loose, re- sembling corn meal in texture, distinctly lacking the smooth, clayey feeling of the finer-grain Leonardtown loam. When wet it packs to a firm surface, which cakes slightly through sun drying. In plowed fields this soil, though distinctly sandy, may clod into large-sized lumps. The subsoil is a reddish yellow sandy loam, finer in texture than the MARYLAND GEOLOGICAL SURVEY 127 surface soil. It extends to a depth of about 30 inches and is almost universally underlaid by a coarse red sand mixed with fine gravel, having an indefinite depth. The soil supports a natural growth of pitch pine, white oak and black oak, and chestnut, this latter tree occurring more frequently on this soil than on any other type represented in the county. The areas of Norfolk loam occurring in the northern portion of St. Mary’s County, particularly in the vicinity of St. Joseph’s Church, constitute what is MECHANICAL ANALYSES OF NORFOLK LOAM. | — : i a Pele |2 3 s gis a =i 42 mo S | = a |e |o | S| 8 |= | Plea edict ese ies: Se | | || @ SE Se Se) Gaul Se No. | Locality. | Description. Ho] a | 28 Me | SH | ow = |s¢8 | | ee Pe ss a= 12 : | 2 |d\e |£|2 |e=| = |e | e | ee se eo We a |S = | —— = Pict. P.ct. P.ct.| P.ct.| P.ct. | P.ct. | Pct. | P.ct 5110 | 23, miles W. of | Yellow sandy | 2.09 2.64 10.04 12.43 | 27.40 12.45 | 23.50 7 Sotterly. | loam, 0 to 10) | _ inches. 5112 | 1 mile E. of New- | Yellow sandy | 1.61, Tr 53 | 2.11 | 36.67 | 18.66 | 31.08 | 9.24 market. | loam, 0 to 14 | | _ inches. | | : 5111 | Subsoil of 5110..... | Medium red sand, | 2.10 | 2.61 12.46 14.35 | 31.94 | 7.78 | 13.89 14.91 | 10 to 40 inches. | | 6113 | Subsoil of 5112..... Red sandy loam, 2.03 0.00 Tr. | 2.38 | 35.11 19.44 | 17.32 23.63 14 to 30 inches. | | | locally recognized as one of the most desirable tobacco soils in the county. The average yield per acre is about 1300 pounds, and the average price about 6 cents per pound. Wheat, corn, and clover are also raised on this soil in regular rotation with the staple tobacco crop. The yield of these crops on the Norfolk loam compares favorably with the average yield of the same crops over the entire area of the county. The above analyses show the texture of the soil and subsoil of the Norfolk loam. The Leonardtown Loum. The most extensive soil type in St. Mary’s County is the so-called white-oak or kettle-bottom soil of the upland. It extends from the vicinity of Ridge post office to the extreme northern limit of the county. 128 THE SOILS OF ST. MARY’S COUNTY The surface is slightly rolling or gently sloping, and the broad, flat divides between the minor streams are covered by this soil. As the soil bears quite a variety of local names, it has seemed best to supplant them all by the name Leonardtown loam. The extensive forests of white oak and pitch pine occurring oyer the upland region are found largely on this type of soil. Where small, irregular depressions without any outlet are found the sweet gum also flourishes. Where the Leonardtown loam is exposed on slopes to the washing action of rains, scalds or washes frequently form and they rapidly encroach upon the arable land. A permanent sod is the only sure cure for these scars, though brush dams cause a temporary delay in the progress of erosion. The cultivated areas of Leonardtown loam vary considerably in the amounts of the various crops produced. Wheat, corn, and grass are best suited to this soil, while tobacco is better adapted to lighter, sandier soils. This soil type forms the nearest approach to the heavy clays of limestone regions that is found in the Coastal Plaim of Maryland. A treatment similar to that employed on the limestone soils should increase the productivity of the Leonardtown loam. The soil consists of a silty yellow loam, fine and powdery when dry, but puddling to a plastic clay-like mass when thoroughly wet. On re- drying, this mass usually bakes to a hard, firm surface, or if stirred before being sufficiently dried, it clods up into hard lumps. The subsoil consists of a brittle mass of clay lenses, lumps, and fragments separated from each other by seams and pockets of medium to fine sand. The subsoil, if evenly mixed, would form a somewhat sandy loam, but its peculiar structure causes it to act like a dense clay in its behavior toward the water circulation. The lenses of clay are slightly flattened and their edges overlap somewhat like the shingles on a roof. Conse- quently, water in its passage through the subsoil, follows a roundabout course along the sand-coated seams. Its progress downward is thus much delayed, and the subsoil is as impervious and as retentive of moisture as a heavy clay soil. he peculiar structure also gives rise to the brittleness noticed on plowing. MARYLAND GEOLOGICAL SURVEY 129 The bright-yellow color of the soil indicates a lack of organic matter. This can be corrected by plowing under green crops and by the applica- tion of stable manures. The tendency toward puddling and baking may be corrected by the application of lime. As has been indicated in the comparison of this soil with the residual soils of limestone areas, the Leonardtown loam is a type best adapted to the production of grass and grain crops, and certain portions of the MECHANICAL ANALYSES OF LEONARDTOWN LOAM. Puneee Saeelmeanice a | Peet lege So len (ee lox aq |S ay Elise WS 5 soles, g u taal | erp Be jos Ss 3 \aa) 3 |gd/ga| 2d] ga] = | od No. Locality. Description. | 89) 5 2 B| 0 | 38 oo | & 83 le |gle |f|8 |e] 2 |e BES een iesee pete ep. aluer eel ieetren |p z et ES ae Eig = og |9 Oo |o |a S |e nan |o és au a | P.ct.| P.ct.| P.ct.| P.ct.| P.ct. | P.ct.| P.ct.| P.ct. 5114 | 3miles W.of Leon-| Yellowsiltyloam, 2.41 Tr 89 | 1.33 5.09 | 11.37 | 58.26 | 19.90 ardtown.......... 0 to 12 inches. | 5116 |1 mile 8S. of Love-| Yellowsilty loam, | 2.24 0.00} Tr. | 3.16 | 17.62 | 18.76 | 47.75 | 9.69 (aU snaces copa con 0 to 12 inches. | | 6118 | 48, miles E. of| Yellowsiltyloam, | 2.97 | Tr. | 1.38 | 1.91 3.87 | 21.90 | 58.46 | 10.06 Leonardtown..... 0 to 10 inches, 5127/2 miles SW. of| Yellowsilty loam, | 2.11| Tr. | 3.05 | 4.19 | 9.79 | 16.54 | 55.70 | 8.03 Newmarket......| 0 to 9 inches. 5115 | Subsoil of 5114.....| Yellow loam, 12to/1.96| Tr.| .76| 1.19 | 5.26 | 18.92 | 55.02 | 21.94 34 inches. | 5117 | Subsoil of 5116..... | melon loam, 12 to | 3.07 | 0.00} Tr. | 3.28 | 9.08 | 11.96 | 49.24 | 22.59 inches. | | | 5119 | Subsoil of 5118.... veluw Loam, 10 al 2.44 -67 | 1.24 | 1.83 | 4.63 | 15.46 | 63.39 | 20.37 inches 5128 | Subsoil of 5127..... Yellow loam, 9 to| 1.56 | 2.22 | 4.78 | 8.49 | 16.97 | 10.77 | 36.42 | 19.20 30 inches, | | area found in St. Mary’s County are at present producing good hay and grain crops. The gradual introduction of live stock should largely increase the producing capacity of this soil, since the crops best suited to the soil can be fed directly to cattle. The saving in the fertilizer bill. in this connection is an important item in farm economics. The above analyses show the texture of the Leonardtown loam soil and subsoil. The Susquehanna Gravel. The layer of gravel which almost uniformly underlies the upland soil types, particularly the Leonardtown loam, reaches the surface along all the more deeply cut stream valleys and along the slopes separating 130 THE SOILS OF ST. MARY’S COUNTY the upland from the low-lying foreland border. The gravel works down across the slopes wherever it reaches the surface, and forms long, narrow bands of a distinctly gravelly soil. While of no great importance either in area or in agricultural value, it forms a marked feature of the land surface. In some instances the component materials are coarse enough to form stony bands and patches along the slopes. In other cases the finer gravel accumulates sufficiently to form small areas of poor or almost useless soil. This is the case on some of the smaller hills of the northeastern part of the county, where broken fragments of iron crust mingle with the gravel and sands. Grapes are cultivated to advantage on similar soils in other regions, and their adaptability to this soil should be tried on a small scale in St. Mary’s County. In general, it would be better to allow forest growths to occupy the larger, more intractable areas. The proportion of gravel in some of these areas is as high as 50 per cent, and with so coarse a texture it becomes almost impossible to main- tain a sufficient supply of moisture to mature any long-growing crop. This is especially the case where the gravel areas lie on steeply sloping surfaces. The Windsor Sand. The Windsor sand areas are found only in the northern portion of St. Mary’s County. They are marked by a strong growth of pitch pine and by the gravelly and sandy texture of the soil. At present these areas are imperfectly tilled to tobacco and grain crops, or occupied by small land holdings devoted to producing garden crops for household consumption. The soil consists of a coarse to medium sand, containing considerable gravel. It extends to about 10 inches in depth, and is underlaid by an even coarser sandy and gravelly subsoil, frequently containing iron crusts in sheets and in broken fragments. The value and capabilities of this soil have not been recognized as yet in this region. Its coarseness of texture, while precluding the profit- able cultivation of grain crops, adapts it especially to the culture of MARYLAND GEOLOGICAL SURVEY at early truck crops and peaches. The latter crop when raised on the Windsor sand produces a superior quality of fruit both in color and taste, and the orchards found on this soil in other localities are long lived, healthy, and profitable. The Windsor sand areas of St. Mary’s County are all located within easy hauling distance of the present railroad points, and special crops of early fruits, vegetables, and peaches could find an easy and profitable market in the cities on connecting lines. The surface of the Windsor sand is generally level and is little sub- MECHANICAL ANALYSES OF WINDSOR SAND. | eae eeepc: | | Sanieee | aes | | s BH lo 19 ° i! 8 S | Ag | jet | ~» So » i=) 35) o o | = a ro 12 co: S Sel cura ised sect see la ees 3g BEN No. Locality. Description. | 83) = ee 2, | oe 238 | = |S | ee | J p a I 19 2 la |gle | fe| 8 | as) 2 | iSenmeaeae firs Sea se |3 a mu 5 © dep cy ot Ss | i6 |e |S |S |= |S | Ble IDeA era enn | Je oha| | Zaxeny || Jeaies|| Wear Vey ty 5129 | Newmarket....... Comige send, 0 to | 1.43 | 5.48 ae 14.04 | 38.63 | 15.16 | 8.10 | 2.76 | 9 inches, | | 5130 | Subsoil of 5129..... Sand, gravel, and | 1.02/ 10.20 20.92 | 12.18 | 29.30 | 11.58 | 10.99 3.81 iron crust, 9 to | | | | 28 inches. | | ject to washing on account of the porosity of the soil. It is easily cultivated and easily improved, and should form a valuable type for the special crops already discussed. The above analyses show the texture of typical samples of the soil and subsoil. The Norfolk Sand. The Norfolk sand illustrates the fact that a single soil type may arise from materials deposited at different geological periods. In St. Mary’s County, soil of this type is found along the sloping sides of streams as an outcrop of some of the basal formations of the county; again it occurs along the lower courses of these streams as flat-topped terraces built up from the older material by river transportation; while small areas of it occur along the forelands as material carried still farther seaward. 132 THE SOILS OF ST. MARY’S COUNTY All these deposits present the same sandy nature and form the same general type of soil, but they vary greatly in geological age. Along the shallow stream channels of the forest area of the county narrow borders of this sandy soil are frequent. In the northern part of the county the streams have also cut into the sandy layer, which is the original source of this material. The covering of other materials has been washed away and considerable areas of Norfolk sand are ex- posed. Wherever found, this soil is recognized as well adapted to the Maryland type of tobacco, and it shares with the Norfolk loam in the MECHANICAL ANALYSES OF NORFOLK SAND. | e 2 sn eerie a I 2 oS | 19 = | S S | = Biypes |S Seales | S | SA Ve hee eel sig 3S. iy 3a 2 [Sale| oq) “2 laa os No. Locality. Description. Eola 52. ae) ae LS 8 a—s-| | iS = | aS) as | BS] So jc | ain eal et |= ara hes |= | 5: | fe | SoV 8 Veale oly onli saeaes Ny bal is} = 1 Mieog la fo) 6 15 = le Vite | eek |S) | | Pct.| P.ct.| P.ct.| P.ct.. P.ct.| P.ct.| P.ct. Pact. 5133 4 miles E.of Leon-| Fine yellow sand,| 1.44 Tr. | 2.74) 7.88 38.57 | 21.77 | 22.387 4.82 ardtown, 0 to 14 inches. 5135 | 154 miles SW. of Medium yellow/ 1.36 1.64 | 8.74 13.60 34.69 18.76 | 15.89 4.87 Hillville. sand, 0 to 10 . inches, | 5134 | Subsoil of 6133...... Medium red sand,| 1.72 Tr. | 2.31) 5.88 34.91 | 20.66 | 22.52 11.96 14 to 36 inches. | | 5136 Subsoil of 5135..... Red sand and) 2.00 4.30 | 12.65 13.69 31.22 10.10 10.12 15.28 gravel, 10 to 28 inches. | reputation of producing a good grade and a reasonable quantity of the crop. The soil consists of a red or brown sandy loam, having a depth of about 9 inches. This is underlaid by an orange or red sand to a depth of 3 feet or more. The natural growth on this soil includes chestnut, oak, and laurel. The Norfolk sand is a typical early truck soil, and has been very successfully farmed in truck crops all along the Atlantic coast. It produces a quick growth and early maturity, and is therefore much better adapted to the trucking business than to the production of grain crops, which require a longer growing season. Peaches, pears, early potatoes, and the common garden vegetables should be raised much MARYLAND GEOLOGICAL SURVEY 133 more extensively than at present upon this soi! whenever transportation facilities permit of marketing. The wild fruits like the blackberry, which flourish so remarkably on this soil, should be replaced by the cul- tivated varieties of the same fruits. The table on the preceding page gives the results of analyses of this soil type. The Sassafras Loam. This soil type occurs in St. Mary’s County at an elevation of from 60 to 90 feet above tide in the form of fiat-topped terraces. It is generally MECHANICAL ANALYSES OF SASSAFRAS LOAM. g 2 [9° Sal a Nee S| e S ad So | £ =I = | | Se || TSI ee) Nh SS als | | Salis ee eee lene: Seam eeedes eee see |e | 2), a | 4 mere So SOM Sessile lea co Ibok No. | Locality. Description. BS) a | eg | 2s | cs o.9 a Ss < a a Es | = Ee 8 = Ss 2 D iS pm S é as | H = ra) b | ; B 0 Ss gs | 3 | 5 a5 3 i | = re) =] ic = — Sp) Tes ite) P= al = | ey eS : P.ct.| P.ct.| P.ct.| P.ct.| P.ct.| P.ct.| P.ct. | P.ct. 5137 | 144 miles W. of | Yellow silty loam, | 2.22 1.21 | 4.51 | 4.57 | 14.94 | 18.26 49.87 | 9.45 Sotterly. 0 to 9 inches. | | | 5139 1 mile S. of Great | Yellow silty loam, | 2.43 1.02 3.12 | 4.53 | 13.35 | 18.14 | 49.68 | 12.80 | Milla: 0 to 9 inches. | | | | | 5138 | Subsoil of 5137..... Yellowsandyloam,| 1.87) .84 4.51 | 5.79 | 22.62 | 10.54 33.84 19.61 | : | 9 to 30 inches. | CATE, 5140 | Subsoil of 5139... |Heavy yellow) 2.17 | Tr. | 2.45 | 4.02 | 13.72 | 12.63 50.56 | 14.16 | | loam, 9 to 30 | inches. completely cleared-and well cultivated. It forms the best corn producing soils of this and other areas and is well fitted for general farming pur- poses. It is formed from a mixture of sand and clay derived from much older strata and reworked and redeposited by stream action. The soil consists of a slightly sandy yellow or brown loam, having a depth of from 8 to 12 inches. This is underlaid by a heavier yellow loam to a depth of nearly 3 feet. This subsoil forms a good storage reservoir to maintain a moisture supply during the growing season without retaining enough water to interfere with cultivation or plant growth. Wheat, corn, and the grasses do well on this soil, while a fair tobacco crop can be raised on it; but it approaches more nearly to an 134 THE SOILS OF ST. MARY’S COUNTY easily worked medium grade of soil for general farming purposes. Pears and other fruits, together with tomatoes, asparagus, and canning crops should be introduced to give a greater variety in crops with increased opportunities for profits. The use of lime and of green manures and stable manures will benefit this soil, though not so essential as in the case of heavier types. The table on Page 133 gives the analyses of Sassafras loam. The Sassafras Sandy Loam. Sassafras sandy loam occupies the low-lying forelands along the Pa- tuxent and Potomac rivers and along the shores of the numerous estuaries and creeks tributary to those rivers. In fact, this soil formation extends as a discontinuous belt of choice farm land almost entirely encircling the county. Lying between the more elevated uplands and the tide-water courses of the chief rivers of the section, the Sassafras sandy loam slopes gen- tly down from an elevation of about 35 feet nearly to water level, and presents a very nearly flat, though gently inclined, surface. Areas located on adjacent forelands are usually separated from each other by lower- lying strips of meadow lands located along the margins of the minor streams. ‘To the rear of each area the surface usually rises with quite a steep slope to the more elevated plateau region. The soil itself is probably a marine deposit, laid down at a time when the relative level of tide water in this region was at least 40 feet higher than at present, though the plateau portion of the county existed as dry land even then. The deposition of material derived from the upland by the streams of that day took place closely adjacent to the land area which existed there, and the coarser sands were deposited in those stream courses as noted elsewhere. The finer sand and silt, carried to a greater distance seaward because of the lightness of individual grains, were deposited in the region of tide water, with the coarser materials falling in shallower water near shore, as is the case with the present deposition in all regions. Thus, small sandbars and spits would be formed, and MARYLAND GEOLOGICAL SURVEY 135 organic matter from the mainland and from the tidal flats usual along low shore lines would be commingled with the sand and silt of the bottoms of the estuaries. In such a manner the sandy loams of this foreland portion of the county most probably originated. As the rela- tive elevation of land and sea changed, this new-formed soil became exposed, and encroaching land vegetation further aided in the preparation of the loam for agricultural purposes. The soil is a dark-brown sandy loam, having an average depth of about 14 inches. The subsoil is heavier, in most instances consisting of a yellow or reddish-yellow sandy loam. At 30 inches depth the sub- soil is normally succeeded by a reddish sand, though frequently this is wanting and a silty drab layer is found, which extends nearly or quite to tide level. This soil is so well recognized as a desirable farming land that all original tree growth has been removed and the area is occupied by cultivated fields. Corn, wheat, and tobacco are raised on the Sassafras sandy loam, and the yield of each is somewhat higher than the average yield for the county. The average wheat crop will consist of about 15 bushels per acre; that of corn about 7 barrels, or 35 bushels; while the tobacco will grow to 1600 pounds per acre, and will sell at 5 or 6 cents per pound. Of course, much larger crops are raised under favorable conditions, while unfayorable conditions of season or culture will corre- spondingly cause a decrease in yield. In the Cedar Point area the production of green peas, tomatoes, and of sweet corn for canning purposes has been undertaken. The climatic and soil conditions are favorable to profitable production of these and other crops classed as truck or canning crops. Along the Patuxent River, near Forrest Wharf, the culture of broom corn is being under- taken. The success of this attempt has not been learned. Owing to the location of this soil along the shore near shipping points, as well as to its texture and general properties, it is well adapted to the raising of fruits, vegetables, and general truck crops which derive value from being placed on an early market. Its position also makes irriga- 136 THE SOILS OF ST. MARY’S COUNTY tion possible whenever the necessity for intensified cultivation shall manifest itself in this community. The general character of the Sassafras sandy loam is indicated by the following mechanical analyses. It is noticeable that the subsoil in each ¢ase contains quite a large percentage more of clay than does the corresponding soil, MECHANICAL ANALYSES OF SASSAFRAS SANDY LOAM. |o No) 4 ° : = | Ws = 3 |2 d 1s =] a Lz Nees es SE lS | oO fate | eee | ae nS | oo ry 5 | [psey ur [Tete ce || feiehileecpisticed|) ao (pee ; e8| 9 |3e|Ss/Ce| ze] S lod No. | Locality. Description. ES|a |e aS Seloo| = |S8 | i) co 4 Tae a fess 12 5 lg |ele (S2\@ || 2/2 3 = H 3 On hee > bm | 80 g ae | © A 5 lied | fe) = Tf Ooi ie) oh Wey, |e & | n |O | | | | P.ct.| P.ct.| P.ct.| P.ct.| P:ct.| P.ct.|P.ct.| P.ct. 5141 1% miles SE. of | Brown sandy loam, | 2.55| Tr. | 1.56 4.39 | 84.34 | 11.86 | 36.62| 8.36 Stone Wharf. 0 to 16 inches, | | 6144 245 miles S. of | Brown sandy loam, | 2.22 | 1.72 | 10.83) 18.96 | 19.85) 6.44) 31.94| 8.56 | Leonardtown. 0 to 9 inches. | | | 6147 | 1% miles NE. of | Brown sandy loam, | 8.50 | 3.49 | 12.80) 9.40| 5.88 | 10.16) 48.62) 6.24 | ‘Trap. 0 to 8 inches. | 5149 | 34 mile NE. of Co- | Brown sandy loam, | 2.93 | 4.87 | 17.49 | 11.83/ 11.08) 9.82 | 30.69) 11.55 | houck Point. | 0 to 12 inches, | | | 5142 | Subsoil of 5141..... | Heavy brown loam, | 1.66 75 | 2.67) 6.79 | 45.80} 5.87 | 17.06 | 19.30 | 16 to 34 inches. | | | 5145 | Subsoil of 5144..... | Red loam, 9 to 30 | 2.58 | 1.58 | 12.36 | 18.69 | 15.99 | 4.62 | 30.43 | 12.80 | _ inches. | | | | 5148 | Subsoil of 5147..... Yellow loam, 8 to) 2.71) .99| 7.03) 6.15) 3.76 | 11.20 51.80) 16.48 | 30 inches. 5150 | Subsoil of 6149..... | Yellow sandy loam, | 2.15 2.98 | 13.72 | 12.18} 9.74] 8.78 | 26.13 | 24.20 | | 12 to 30 inches. | | The Meadow Land. The natural meadow lands of St. Mary’s County are usually flat or gently inclined areas occurring along stream courses or on the low, flat forelands bordering the tide-water areas. The meadows are usually rather wet, and in many instances they differ from adjoining soil types in their relation to drainage rather than in their texture. The natural forest growth over the meadows includes white oak, willow oak, sweetgum, and poplar, with frequently a matted undergrowth of shrubs and vines. The meadows furnish a rather coarse, rank grass for grazing and, owing to the mild climate of the region, cattle frequently find pasturage throughout the winter. MARYLAND GEOLOGICAL SURVEY ISH The large meadow areas of the forelands are frequently cultivated to the general farm crops, but in wet seasons they are difficult of tillage, and even in the most favorable seasons they produce only wheat and grass to good advantage. They require extensive underdrainage; even open ditches are inadequate, for the soil is so dense and so near water level that surface drainage fails to lower the level of standing water sufficiently to aerate the soil thoroughly. The presence of excessive water in the soil thus tends to keep the ground cold and to delay seed germination and plant growth. Then, too, the organic acids tend to MECHANICAL ANALYSIS OF MEADOW. | Le} re} ° ton] jo i Ss Sie |lbses | 3 Raaea ie. eelees |e aalca: |S H g = 2 ag Bg|/a2 | © $ |= /3./s8/8.|8e| =| 2 | a 2 S| og 8 BAS | | ae 2 | 10 | No. Locality. Description. HSo| = | s8|e|/sa|/ oe] = | Ss oO = Al oe q-] iS 10 ==! 2 EO esi iee | os = he = o b eS SS | ra Es 2 © p= | ee aS, ° Sars. A fe |-F a | © | | P.ct.| P.ct.| P.ct.| P.ct.| P.ct.| P.ct.| P.ct.| P.ct. 6151 | 2 miles SE. of Bris- | Gray loam, 0 to 8 1.84) Tr. 88 83 | 3.76 | 23.35] 69.59) 9.58 coe Wharf. inches. | | 5153 | One-eighth mile W. | Brown silty loam, | 2.32 | 1.41 | 3.33 | 4.12 | 6.46 |15.41/ 58.54) 8.32 of Short Point. 0 to 7 inches. | 5152.) Subsoil of 5151...... Draprolaye 8 to 30 | 2.89 | 0.00} Tr. | 1.73 | 5.38 | 16.30 47.50 | 25.77 | inches. | | 5154 | Subsoil of 6153...... Deabiclay, 7 to 32 | 1.61 |; Tr. | 2.01 | 2.61 F.11 | 11.40 60.11 14.74 inches. | | | | accumulate to excess, proving harmful to plant life and not fulfilling their function in the preparation of mineral matter to serve as plant food. Proper underdrainage by lowering the water level will not only drain off surplus moisture, but will also permit a circulation of air, and thus aid in the natural improvement of the soil. Many thousand acres of meadow land, now producing only a rank growth of grass or an uncertain crop of grain, can be made highly valu- able by relatively cheap methods of underdrainage. The soil of the meadow areas usually consists of 8 to 10 inches of gray silty loam underlaid by a subsoil of ash-gray clay loam. The soil mass is apt to be cohesive and clay-like when wet, but when subjected 10 138 THE SOILS OF ST. MARY’S COUNTY to the action of the frost and air it becomes powdery and crumbly, and is very much improved in texture. Drainage and liming should be resorted to in order to produce this result on a large scale. The texture of this soil is shown by the analyses on Page 137. The Swamp Land. There are three types of swamp lands in St. Mary’s County—the tidal flats, which are wholly or partially submerged at each high tide; the fresh-water marshes, subject to frequent or constant inundation by streams; and the fresh-water bogs and swamps, due to incomplete head- water drainage or to natural or accidental artificial ponding of stream waters. The salt marsh at the head of Chaptico Bay and the flats at the head of Breton Bay are the most extensive examples of the first class occurring in St. Mary’s County. Except at especially high spring tides these areas lie about 5 feet above the water level. They support a growth of marsh grass and reeds and possess a silty soil mixed with partially decayed vegetation. Some marsh hay is cut over these areas, and cattle and hogs find pasture where the surface is sufficiently firm to support their weight. These marshy areas are formed by the deposition of fine sand, silt, and clay, brought down by streams and by the higher tides, together with the decaying remains of the vegetation which gains a foothold on the drier areas. These marshes are constantly growing in extent, and in many instances cattle are feeding on marshy meadows where small- sized boats floated in the early days of the colonization of the county. Farther from the mouths of the larger tributary streams, above the highest reach of the tide, the fresh-water marshes occur, as is the case along the Chaptico Creek, McIntosh Run, and many of the streams flowing into the Patuxent River. These marshes are similar to the salt marshes, except that they are only subject to irregularly occurring inundations below fresh water instead of periodic submersion by the tides. The third class of swamps occupy positions at the heads of some of MARYLAND GEOLOGICAL SURVEY 139 the main streams and along the upper courses of the majority of the smaller ones. The headwaters of the St. Mary’s River drainage, found in the forest area around St. Andrew’s Church, illustrate this condition markedly, though many other localities are very similar. The surface in this forest area is slightly irregular and consists of Leonardtown loam and Norfolk sand. The hollows in both of these formations are swampy and grown up to gum trees. In wet seasons small ponds exist, which become dry, or nearly so, during the latter part of each summer. A slight clearing out of the natural drainage ways, connecting these ponds with stream courses, would destroy the ponds in most cases. Frequently the obstruction to drainage consists of a rank growth of vegetation, fallen tree trunks, and the accumulation of dead leaves and soil wash. In some few cases the grading up of highways or embankments constructed for proposed railways through the county has caused accidental artificial ponding of waters. These are of small extent and may be easily remedied by underdrainage. Tue AGRICULTURAL CONDITIONS. The condition of agriculture in any community depends upon four factors—soil, climate, transportation facilities, and the mental and physical energy of the population. The first two of these factors are natural, while the last two are to a great degree artificial. Usually it does not lie within the power of any community, however energetic, to modify the soils or the climate of a region to any marked extent. The great exception to this statement is in the arid states, where irrigation has been introduced, transforming desert areas into fertile farms. The actual conditions of the soil, the climate, and the transportation facilities of St. Mary’s County have been treated separately in other chapters, but a general resumé of the interrelationships of these factors and a slight reference to certain social and economic conditions prevailing in the county are necessary to a full appreciation of the present status of the county by its own inhabitants as well as by strangers. The usual farm practice in St. Mary’s County is based on a rotation of crops, including tobacco, corn, wheat, and grass, or a season of fallow- 140 THE SOILS OF ST. MARY’S COUNTY ing. This rotation is observed on all soils in all parts of the county, though some individual farmers have modified it. Thus, in a great majority of cases, the fundamental factor of soil differences is neglected. The success of the rotation in the county has depended upon the highly accidental factors of the location of the farm and the energy of the farmer. Thus, the energetic man located on the proper soil for the tobacco crop will be highly successful, while his no less energetic neighbor located on the wrong soil may be unsuccessful, and the unenergetic man may absolutely fail. The natural selection of farm lands dependent upon these conditions has led to the abandonment of large areas of the Leonardtown loam to forest occupation, for the soil is not adapted to the culture of the quality of tobacco which buyers expect from the county. On the other hand, the Norfolk loam is tilled over almost every acre of its extent, because it is adapted to the production of this chief crop. In the same way natural selection has led to the extensive cultivation of the Sassafras sandy loam, and it is worthy of notice that the very first white settlers, as well as their Indian predecessors, located on this soil type chiefly because of its location near water transportation, but also probably in part because it is an excellent soil for general farming pur- poses. Contrasted with this soil are the large areas of meadow land still clothed with forest growth, though similarly located to the Sassafras sandy loam. It is not entirely an accident that leads to these selections and to the introduction of new crops, such as peaches, on the Norfolk sand, or to the cultivation of canning crops and broom corn on Sassafras sandy loam. ‘The climate of the region is suited to the crops, the soils are similar to those upon which the crops have been raised elsewhere, the facilities for transportation are in part equal to the necessities of the crops, while the energy required for their introduction is supplied by well-informed and progressive citizens of the county and of other regions. A local and partly defined soil classification has been reached through this process of selection, though the areas suited to certain crops have not been located nor mapped over any part of the county until the present time. Nevertheless-experience, often bought at a dear price, MARYLAND GEOLOGICAL SURVEY 141 and confined to the few who have ventured their money and their time, has led to the partial classification already noted. It is hoped that the classification, the map, and the description of soil types contained in this report will facilitate further development along the lines of soil selection for special crops, will encourage the introduction of new crops, and will lead to a generalization of the experience gained by the few for the use of the many. Closely associated with the adaptability of certain soil types to certain crops is the two-edged question of fertilizer, which is dependent for its answer upon the quality of soil to be fertilized and the kind of crop to be raised. Probably every soil type in St. Mary’s County contains within 4 feet of its surface sufficient plant food to produce 100 crops of any kind which are raised or could be raised in the county. The necessity for fertilizer depends on the fact that much of this material is present in such chemical combinations and in such a physical state that some manipulation is required to release it and to bring it into solution in water so that the plant roots may absorb it. Certain chemicals found in commercial fertilizers and in stable manures tend to release this plant food and to form or supply soluble chemical compounds suited to the needs of the plants, while organic matter constitutes the best sponge for retaining the absolutely essential water supply in sandy soils, and acts equally well in loosening the too closely packed particles of heavier clay soils. The organic matter, through its decay, also furnishes actual plant foods and solvents for the preparation of other foods. The character of growth desired in special crops modifies the kind and amount of special fertilizers for those crops. For example, it is a generally accepted principle of tobacco culture in Maryland that liming land spoils the texture of the tobacco raised, causing it to spot and injuring the burning qualities for which it is so well known; therefore the use of lime on tobacco lands is precluded, though its use would be of undoubted advantage on all of the heavier soil types and upon most of the lighter types for other crops. St. Mary’s County possesses large stores of carbonate of lime in the 142 THE SOILS OF ST. MARY’S COUNTY Miocene marl beds underlying all of the upland portion of the county and reaching the surface in nearly every cliff and stream cutting over the upper half of the region. This lime supply consists of the calcareous tests of marine shellfish which once lived upon the sea bottom when the ocean covered the county. The shells, buried in sand and elevated above water level, can be dug out by the wagonload and converted into excellent lime by sieving out the sand and burning the remaining shells, just as lime rock is burned to lime. The sifting would be unnecessary in the case of some of the deposits, since the small amount of sand present would be a benefit to the heavier types of land. The Leonardtown loam would benefit materially from such liming, except, of course, when tobacco is to be raised. The plowing under of green crops, especially the leguminous plants of the clover and cowpea varieties, furnishes another method of enrich- ment highly desirable on almost all the soil types of St. Mary’s County, and does not present the difficulties of liming, since this kind of fertilizer is of great benefit to the tobacco crop. These leguminous crops furnish a fair forage for cattle during a period of their growth, and if allowed to continue growing they produce a mass of organic matter for incor- poration with the soil; and all the time, beneath the surface of the ground, certain minute bacteria, living on the roots, are taking nitrogen from the air and storing it in the soil, thus helping its enrichment. The ordinary practice of putting from 200 to 400 pounds of commercial fertilizer, costing from $18 to $40 per ton, upon the farms of St. Mary’s County has a double effect. It produces the crop, but it also enters a large item on the expense side of the farm account, and on some soils its continued use has the effect of burning out the soil, so that periods of fallowing become essential. For certain crops special fertilizers will always be necessary, and commercial fertilizers are to be commended highly, but in St. Mary’s County on all soils the use of stable manure and the plowing under of green crops are to be preferred, while on the soils least suited to tobacco the abandonment of that crop and the free use of lime in conjunction with organic matter have already become necessary, as is shown by the forest areas given over to nature’s cultivation. MARYLAND GEOLOGICAL SURVEY . 143 Many of the farm buildings of St. Mary’s County are of remote date. The farmhouses particularly are types of colonial structure, and the residence upon the farm at Sotterly is one built for the first governor of Maryland, while numerous other manor houses in the county are nearly as venerable. Even the less pretentious houses display the long sloping roofs, the gable windows, and the large end chimneys of the early colonial period. The atmosphere of antiquity, of romance, and of his- toric interest which surrounds these old residences and the equally ven- erable churches and farm properties gives a local color and a local pride to the county that can be shared only by other communities of equal age. Outbuildings are not so essential in this climate as in regions of heavier snowfall, so the older farms are provided only with the tobacco barn, smokehouse, and corncrib of the plantation, the large stock and hay barns being almost totally unknown. Cattle can graze upon the meadow lands in all but exceptionally severe weather, and the side of some existing building or the shelter of woodland protects them during the coldest weather. The fences are mostly built of rails and poles cut in the native forests, though some barbed and other patent wire fences have been introduced. The Virginia rail or worm fence is the most common type, while the mortised post, into which the ends of the rails are fitted, is also common. No account of the condition of agriculture in St. Mary’s County would be complete without a reference to the common draft vehicle and beast. Owing to the steepness of the grades and to the general difficulties attend- ing land transportation, the ox-cart is usually employed for heavy hauling. It is no uncommon thing toward the latter part of June to meet from one to twenty 4-ox or 6-ox teams attached to heavy 2-wheeled carts, upon which one or two tobacco hogsheads are being drawn to the wharves for shipment. Each hogshead constitutes an unwieldy mass of about 800 pounds of tightly packed tobacco, and the successful transportation of some of these loads down the steep slopes from the upland to the wharf, under the existing road conditions, is no small feat of engineering. The field labor is largely performed by the numerous colored population of the county, some of whom labored as slaves on the same farms where 144 THE SOILS OF ST. MARY’S COUNTY they now work as free men. The majority of the workers, however, be- long to a more recent generation. There are no large towns in St. Mary’s County. Leonardtown, the county-seat, is the largest, while Mechanicsville, at the terminus of the railroad, does a thriving business, and Charlotte Hall is the seat of a well-known school of the same name. The tendency of the white population is toward the enjoyment of the seclusion of large estates, and frequently the manor house or farmhouse is reached only by a long avenue leading away to a distance of nearly a mile from the public highway. On the other hand, the colored popu- lation segregates into little communities, where land may be obtained cheaply, and little villages of frame and log dwellings are dotted over the county. THE TRANSPORTATION FACILITIES. A single branch line of railway, connecting Mechanicsville with the main line at Brandywine, is the only rail communication between St. Mary’s County and the markets and cities of the State and the country at large. This lack of railroad communication is partly relieved by the steamboat service on the Patuxent and Potomac rivers and on the larger streams. As two lines connecting with Baltimore and Washington control the water transportation, this can scarcely be said to equal the needs of the county. The boats run only at long intervals and at rather irregular times, and the trip to Baltimore or Washington consumes from sixteen to twenty-four hours, depending upon the volume of freight carried. For this reason the crops produced in the county are placed at a dis- advantage with relation to markets when compared with those of other regions, and the variety of crops that can be raised with profit is con- siderably restricted. This is particularly evident in the case of fruit and truck crops and of dairy products. The truck lands of St. Mary’s County are excellent, so far as soil and climate are concerned, but no one cares to enter into their cultivation to any extent so long as the cost and uncertainties of marketing remain as great as at present. Again, MARYLAND GEOLOGICAL SURVEY 145 the Leonardtown loam, the Sassafras loam, and the meadow lands are well adapted to dairying and to stock raising, but the time distance from markets and the actual uncertainty of any communication during win- ter months retard or prevent introduction of stock. The waterways for extensive steamboat communication exist, grades well adapted for railway construction are to be found, and the con- struction of the roadbed presents only the simple engineering problem of cut and fill, with no consolidated rock formations to require blasting. The soils, the climate, and the natural advantages of geographical loca- tion all favor the upbuilding of the county. It is likely that outside influences have combined with a well-defined conservatism in the native population to retard the development not only of this but of other locali- ties in the general region. The internal communications of the county consist of highly varied wagon roads. The main roads follow the main divides, while public and private roadways lead out along the secondary divides and down to the lowland farms and to the wharves. Bridges are scarce, and the small streams are crossed by fords. The tide-water indentations along the coast and the marshes at their headward extremities separate the farms along the forelands, and it is possible to go only from one foreland to another by considerable detour inland, usually including a steep ascent to the upland and an equally steep descent to the adjoining foreland. Foot passengers can usually find a small boat to transfer them across such obstacles, and many of the farmers own sailboats, but regular ferries do not exist. There is no regular ferry or bridge across the Patuxent terminating in St. Mary’s County. The wagonroads consist of sand, loam, or clay, as they happen to cross such materials, and the rain wash and the wear of travel have cut the roads down for long distances far below the surface of the country. In many places where the roadway has been washed to a state of impassability teams have driven around the gully and established a new highway, or an overturned tree is ayoided similarly. One road district in particular has secured fairly good roads partly through the 146 THE SOILS OF ST. MARY’S COUNTY energy of its supervisor, partly because additional contributions above the annual tax have been given by residents of the district, and partly because the district contains better road materials than some others. The iron-stained gravels of the upland plateau should be used to a greater extent in surfacing its clay roads, but proper drainage and grading of most of the roads must precede any other work. (ine CLIMATE: OF ST MARYS COUNTY BY C. F. VON HERRMANN INTRODUCTORY. The extreme southern boundary of Maryland is located at the mouth of the Potomac River, near the Virginia shore, in latitude 37° 53’ N. Point Lookout, at the southern extremity of St. Mary’s, is only a few miles farther north, and the region whose climate is to be discussed in this chapter, thus forms one of the most southern counties of Maryland. As the county is distant from the mountains, its surface level, and its coast line deeply indented by rivers and tidal estuaries, it is apparent that the factors immediately controlling the character of its climate are its relatively low latitude (38° 2’ to 38° 31’ N.) and the proximity of large bodies of water. The mitigating influence of water on climate has been sufficiently discussed in the chapter on the climate of Calvert County to which the reader is referred. In that sketch it was shown that the waters of the Bay and Atlantic Ocean have much less influence than might be expected on account of the prevailing off-shore winds. It was also shown that as the cold Labrador current flows near the Atlantic coast the waters bathing the shores of Maryland and the interior waters of the Bay are below the temperature normal to the latitude. The popular belief that the Gulf Stream itself has an influence on the climate of Maryland is quite erroneous. The temperature of St. Mary’s County will probably be found to be slightly higher than that of its northern neighbor, Calvert County, but its northwest portion, which is farthest removed from the Bay will have a large range of extremes. In the present study of the various meteorological elements the inquiry should be kept in mind to what extent does the climate of 148 THE CLIMATE OF ST. MARY’S COUNTY St. Mary’s County differ from what may be designated the normal for its latitude. This region shares all the characteristics common to the coastal plain, the most important of which, from a climatic point of view are, its low, level surface, its unconsolidated soil of sand and clay, and its con- siderable area of forests. The peculiarities of the drainage in this region is remarkably well shown in St. Mary’s County. The water-shed lies very near the valley of the Patuxent River the entire distance from Charlotte Hall to Jarboesville, and farther south it continues quite near the Chesapeake shore. Thus the rivers drain south and southwest into the Potomac, at right angles to the general direction of drainage in the Piedmont Plateau. The general elevation is somewhat over 100 feet, approaching 200 feet in places. Isolated elevations of over 100 feet are found even in the extreme southeast portion of the county, for instance near Friendship, which is a few miles from the shore, north of Point Lookout. The level areas of 100 feet elevation are more num- erous and broaden out toward the northwest portion of the county. All the meteorological stations, except Charlotte Hall (167 feet) have an elevation of less than 50 feet, that is they are situated on low ground at the head of small bays. Curmatic Data AVAILABLE. Although climatic records are available for seven stations in St. Mary’s County, the periods of observations are all short and much broken. The earliest observations in the county were taken under the auspices of the Smithsonian Institution, by Mr. T. G. Staggs, at Ridge, from 1856 to 1857. Other early records are those by Dr. Alexander McWilliams, at Leonardtown, from 1858 to 1859, and by Rev. James Stephenson, at St. Mary’s City, from 1859 to 1870. At Cherryfields (P. O. Valley Lee) observations were taken by Col. J. Edwin Coad for a period of five years, from 1893 to 1899. The rainfall records for St. Inigoes taken by Mr. James F. Ellicott, from 1871 to 1879, must be used with caution. For all of these stations only the mean temperatures and the monthly precipitation are available. The only fairly complete record MARYLAND GEOLOGICAL SURVEY 149 for St. Mary’s County is that for Charlotte Hall in the northwest portion of the county. Here Prof. J. Francis Coad took meteorological obser- vations from 1893 to 1904, but owing to frequent absence from station the records are unfortunately not continuous, varying in length from 7 years for June to 11 years for January. Table XXIV, page 176, gives the necessary information in regard to each station in the county. St. Mary’s City, St. Inigoes, Ridge, Cherryfields, and Porto Bello are located not far apart in the southern portion of the county, near St. Mary’s River; Leonardtown is at the head of Breton Bay; and the most northern station, Charlotte Hall, lies near the boundary of Charles County. From the fact that records of temperature extending over many years, such as the period of 200 years at Florence, 100 years at Paris and 88 years at Baltimore, show no change from the annual course of tem- perature at present observed, in spite of the great variation in the monthly means, it is concluded that every place has a normal march of temperature which can be ascertained only by a series of observations of considerable duration. The length of the period required to obtain a correct normal depends largely upon the character of the climate. In tropical regions where the seasonal variations are small, five years are sufficient to give an annual mean temperature accurate to within 0.1°, but such is by no means the case in a variable, continental climate like that of the eastern United States. At Baltimore the probable error of the means for 88 years is still greater than 0.1°. Means for less than 20 years at any station in Maryland are far from representing true normal temperatures. At Baltimore the January mean temperature has varied from 438.9° in 1858 to 24.3° in 1893, a difference of 19.6°; at Solomons the variation in the February means was from 40.8° to 26.2°, a difference of 14.6° in 14 years. ‘Therefore, in comparing short term records at several stations it is impossible to determine whether the differences observed are really due to actual differences in climate, or are due to the special character of the short period from which the means were derived. This is well shown by comparing the excellent record for 14 years at Solomons (1892 to 1905) with the 88 year means at Baltimore, when it appears that Solomons is colder than Baltimore 150 THE CLIMATE OF ST. MARY’S COUNTY in January and February, an entirely erroneous conclusion; for by comparing the Baltimore and Solomons records for the same period of years, the proper relation of temperature for the two stations becomes at once apparent.’ Mean temperatures for short periods may, however, be corrected, when there is available for comparison a long record at a station not far distant, and similarly located with respect to its topographic surround- ings. For Lamont has shown that in spite of the variability of the temperatures from month to month, the differences between neighboring places remain constant. These differences are fixed by physical causes and so may be strictly considered a meteorological constant (Hann). Baltimore is not very differently situated from other stations in southern Maryland, and its record for 88 years may be used as the criterion by which to ascertain the corrections to be appled to short term records to obtain the true normals. The application of the method may be conveniently illustrated by an example. The January mean temperature at Baltimore (88 years) is 34.9°; the January mean for Charlotte Hall (10 years) is 34.0°. Charlotte Hall is 56 miles south of Baltimore, and cannot normally have a lower mean winter temperature than Baltimore. The correction to be applied is calculated as follows: =. _— ————e ee 5 | 1894 | 1895 | 1896 | 1897 | 1898 | 1899 | 1900 | 1901 | 1902 | 1904 | Means. Charlotte Hall...... FOCUS 38.6 | 32.8 | 83.6 | 33.2 | 38.3 | 34.2 | 36.3 34.4 | 31.6 | 29.8 34.09 Departures .......++ see-| 4.6 |—1.2 |—0.4 |-0.8| 4.3] 0.2] 2.3 | 0.4 |—2.4 [4.2 2.20 1syNiFborOdevouyoadddcd Goquoaue | 37.4 | 31.4 | 33.3 ) 30.8 | 36.7 | 82.7 | 35.8 | 34.4 | 31.5 | 27.4 32.82 Difference*........eeeese+s | 1.2 | 1.4] 0.8] 9.4] 1.6] 1.6] 1.0] 0.0) 0.1] 2.4 1.20 Departures ........+se0.: 0.0} 0.2 |—0.9] 1.2] 0.4] 0.8 |—0.2| 0.0 |—1.1] 1.2 0.19 2 Difference between Charlotte Hall and Baltimore. This first column of departures is the departure from the average of the mean temperatures; the last column of departures is the departure from the normal of the differences between Baltimore and Charlotte Hall. The average of the variations of actual mean temperatures at Charlotte Hall is 2.2°, with a probable error for the 10-year period of plus or minus 0.6°; but the average of the variations in the differences between 1See the chapter on climate in Calvert County Report. MARYLAND GEOLOGICAL SURVEY 151 the Baltimore and Charlotte Hall means is only 0.1°, or twenty times less, and the probable error is only plus or minus 0.03°. As the mean for January at Baltimore for 88 years is 34.9°, and Charlotte Hall is normally 1.2° warmer (probable error 0.03°) the corrected January mean for Charlotte Hall is 34.9° plus 1.2°, which is equal to 36.1°. The corrected mean temperatures given in Table I have all been ascertained in this way. In order to secure a fairly accurate mean temperature for St. Mary’s County, the corrected means for the following stations have been em- ployed, viz.: Charlotte Hall (9 years’ record) situated in the northwest portion of the county, Cherryfields (5 years), St. Mary’s (7 years), and St. Inigoes (7% years) in the southern portion of the county, and Solomons (14 years) near the middle of the northern shore. THE TEMPERATURE CONDITIONS. The average monthly and annual mean temperatures corrected as indicated are given in the second part of Table I. The upper portion of the table contains the original uncorrected data for all stations in the county. The annual mean temperature for St. Mary’s County is found to be 57.1°. This is slightly higher (0.3°) than the mean for Calvert County. Spring (55°) and autumn (59°) have the same tem- perature as Calvert County, but summer (76°) is about a degree cooler, and winter (38°) a degree warmer, a difference which may be attributed to the superior influence of the Bay. The warmest month is July, with a mean of 78°, and the coldest January, with 37°, giving an annual range of 41°. The extremes in St. Mary’s County are, maximum 104° at Ridge in July, 1856, and minimum 19° below zero at Charlotte Hall in February, 1899." The range in absolute temperatures is 123°. Maximum temperatures of 100° or above have also been recorded at Charlotte Hall and St. Inigoes, and 2° below zero occurred at Leonard- town during the cold winter of 1893. The monthly mean temperatures at all stations are given in Tables II, III, IV, V, VI, VII, and XV. ?See the remarks in regard to this record on page 168. “AJuNOD JAaATeD Ul, “SUO!}BAdOSgO ‘ul ‘dG pue “uM “d Z “WM “BY JO SUBATN » ‘a dG pue “ud Zu "ey YB SUONRAIASqG "ploda1 AILIUOMISBAT 9 "COG URs0q ‘sav “}8 eTS0ddO y “‘SHOnUT}UOD JOU Spaod0y g ‘oa. flajyjDA SB owLg “Wd g PUB “UI ‘LY g 4B SUOT}RAIASqO ; *}X0} OY} Ul UOT}eULldxG , 9°F9 | 49 | 9°6E | 6'8F Oho | GLO | 8°6E | FGF 8°99 | SOF | eT org OOF OF 9°49 T6e | 4°6F | 6°9L | BLL | OSL | GF9 T'8h | 8°6L | O'FL | 6'F9 GOL | FLL | OSL | 0799 QLL | 9°9L | O'8h | 0°69 9°9L | T'8L | 9°SL | F'F9 G06 T-G68T . MARYS COUNTY ST. 9°F9 | €°9g | 6°9F QOL | LLL | 8°Sh | FO 4 Se ee Ne cat | | ee el ee ies = BS fey | rn ay a 2 So | oso fe = | 6 & 5 85 + 5 ® o 2. By 4 ® : 3 S09 3 5 i=] fom @ = . > es cat ® 1S = B B ® B tet aS F © F o o n = ‘ ‘ r & 23 g ° a f ie} 30 “SUDVUGAY ALNOO) GNV ;SNVOI Guanorur0D tees|ereeseseces KQuNOO OY} LOT +++, SUOULO[Og 6LET-TL8T (aie eleies cieistect seis tiea FQ Q.8 TUL Tat OLST-6¢8T see eeee were oe 8 AIR] 49 BOSL-G68L [occ sprog Maaaqg Qoel-cesh |otc [TRH oopaRyg, “SaBOK “SUOTTRIS THE CLIMATE OF TCE | 0°O8 |O[FG'SEF'6L T'LG | 4°6L |8'GhG'9E)0' SL 9°96 | OBL |O'8E/9"LEG OL 6g | Vhs 6 THe PE TOL 8'°9G | BIB OEP PSO LL) (O'°SEG' 6S 6°89/9°89/T'OL1F 6L/8°E116° F9 8°19/9°OL/0°8L/1°9L/9°SL/6'°T9 “|LF8|8"8L/Gg°a9 sete" *"15°0L/6"°9L/0'6L/8 "SL 6 FFF 9910 69/9 OL/F'9L)0°SL10° C9 LPG LOB OLE GAIT 'OL/8* Chia" F9 O'9F/F'L9/9OL)G'9L/0° LL10°SL LORT-OG8T | $99 |leteiein¥eibiae) sons teeta se O08 0F10g 668T-E68L | S06T-G68T oa 0 XH A PO fete reer reenter SQORTUT IS eee wee QUGRAUE TOIT RAG TD Al 49 9 OSDIT titers ereee ees + +0 TL MO] pPIBUOAT siejejeie(0/6 a/aieieiv'e reese sproysatoyg SeeveesereeeccesecectiBET OFF 0]IBYO aqnjosqy | “TON UIX BY aqynposqy “WINUIIUT | | | “UBOW | Saleen So) — KSI Soom] ® |OLIo pSa/Pps) §= ipais aeo\5a¢2) % |4q ag Foa|' FO o |ralr ae) ae 3s | -aaquieoe(T “OQUIJAON ou c i= is “1aqo1vo ~1aqmieydasg “AINOOD S,AUVW “LS ‘VV auNLyuddWaL ‘T GTdava “pro0oay joqysue'y ‘aun “ARV “Arenue *SIBNAQOT *suolyeIg MARYLAND GEOLOGICAL SURVEY . 153 TABLE II. MONTHLY AND ANNUAL MEAN ‘TEMPERATURES! aT CHERRYFIELDS, Mp., 1893-1899. West coal) Z Year. ket eee WS eels | RaSoa ear ran een ra Ua y El fo a|/ ea) 6s 5 S 3 Sill oo ° Ss) a Paes = |< = 5 5 < va a) Z a 4 1 Observations at 8 a. m. ana 8 p. m, TABLE III. MONTHLY MEAN TEMPERATURES AT RIDGE, Mp. Year. Nov. 3 =| : a | a July. Aug. Sept Oct Annual. Pe ear lsdeyael become | GRO tcc .| 26.6 | 43.3 | 41.8 | 49.6 | 63.2 IrOu ease rere cr | 73.1 | 59.2 | org ail|eares. (vec beset [Re ye [bisa Table I and subsequent tables containthe monthly and annual mean tem- perature and total precipitation at all stations in St. Mary’s County. Table XXIV gives the necessary statistical data. The following remarks are pertinent: The observations at Charlotte Hall were commenced by Mr. R. W. Sil- vester in 1892, but were continued by him for less than a year, therefore, the larger portion of the work at the station is credited to Prof. J. F. Coad. In 1905 Rey. J. Neilson Barry became observer at Charlotte Hall, and it is hoped a new and valuable series of records will be secured for that station. At Cherryfields the temperatures were observed at 8 a. m. and 8 p. m.; the means given in Table I, are the original records, but the corrected means were reduced to the equivalent of maximum and minimum readings by applying a correction determined by the difference between the means from 8 a. m. and 8 p. m., and from maximum and minimum temperatures at Balti- more. At Leonardtown the means are from observations at 7 a. m. and 2 and 9 p. m. These have not been corrected to the means of maximum and minimum temperatures because the differences are very small. As regards precipitation the records at St. Inigoes are of doubtful value; at Charlotte Hall the irregularity of the record causes the rainfall to come out too small for the period. 11 154 THE CLIMATE OF ST. MARY’S COUNTY TABLE IV. MONTHLY MEAN TEMPERATURES AT PORTO BELLO, MD. | a a 4 | - | g Y ; Bt ieee ye Se) a) a Ws] 8 yes Wes || ear EI oy Mee See eh tet er RRP gs Ih oth sey |) iE 5 is = < cay is i) < nm fo) a a < | | | | AT BOB temiaiereisceieloetes ete | 31.3 | 28.2 | 46.5 | 54.0 | 66.8 | 73.8 | 79.0 | 76.2 | 70.4 | eafelesat | istetaet | Radgs | poodad TABLE V. MonTHLY MEAN TEMPERATURES AT LEONARDTOWN, MD. a eal FY a g Year. Fao cme tesallesh ea | Sh os Le is ls) 5 © & = 3 5 5 5 ay ° ° a | S | & = sh} Ct 5 = < 2) ° a a < | 0 8.0 8.2 72.0 | 76.4 | TABLE VI. MONTHLY AND ANNUAL MEAN ‘TEMPERATURES? AT ST. Mary's, Year. Mp., 1859-1870. | | Dec. Annual. to 9209 YD SHe 3 Highest Means Lowest Means Range....... 1 Means from 7 a.m., 2 p. m., and 9 p. m. observations. MARYLAND GEOLOGICAL SURVEY 155 TABLE VII. MONTHLY AND ANNUAL MEAN TEMPERATURES AT St. INIGOES, MpD., 1871-1879. a| a | | = Year. hg [he q | B Se |Site te sep liao esta Bs 3 a ene aan eae Sees igre ete eo) 7 Os eo. | ist lee & = <4 2 /e]r a0) ANPUSt.) 1864, 27.1° in January, 1867. 1From observations at 8 a. m. and § p. m. uncorrected. The highest monthly mean temperature in the county was 84.1° in July, 1856, at Ridge, and the lowest was 25.6° in January, 1893, at Leonardtown, giving a large range of 58.5°. THERMAL ANOMALIES. We may now inquire what relation does the corrected mean tempera- ture for St. Mary’s County bear to the normal temperature for its latitude, in which the effect of the distribution of land and water peculiar to the region in question may be considered to be equalized, if not elimi- 156 THE CLIMATE OF ST. MARY’S COUNTY nated? The well-known isothermal charts showing the distribution of temperature over the globe are constructed by entering on a chart of the world the mean temperature for each station reduced to sea-level, and drawing lines through points which have the same temperature. From these charts it is possible to calculate the mean temperature of each parallel of latitude. The mean temperature for equidistant points on each parallel is ascertained, for instance, at the crossing point of every 10 degrees of longitude, giving 36 values, the average of which is the normal temperature for the parallel. This normal may be viewed as the temperature which would result at the given parallel from an equable distribution of land and water, instead of the irregular dis- tribution found in nature. A comparison of the actual mean tempera- tures observed with the normal for the latitude will show whether a region is warmer or colder than the normal or the thermal anomaly of the region. The parallel of 38° N. is the nearest to St. Mary’s County. The mean temperatures for this latitude, as found by Spitaler, and the correspond- ing means for St. Mary’s County are given below: Annual Mean January July Temperature. Mean. Mean. Parallel Of * SS oe Nene .arpetlesy eters ie 59.5° 44,2° 76.5° St. Mary's: (County.o-« snc ce ciclecicis SieLe Sia bo 17.8° DDE T ENCES a eyere ctssesaiatelsiovatelsystereiete —2.4° —7.1° +1.3° The comparison shows that the annual mean temperature of St. Mary’s County is 2.4° lower than the temperature proper to its latitude. The thermal anomaly is negative throughout most of North America (except the Pacific and Gulf coasts) and the deficiency exceeds 7° in the region northwest of Hudson Bay. In winter St. Mary’s County is 7.1° colder than the normal for its latitude, or in other words the character of the year is determined by the severe winter climate of the great continental interior. North of the Lakes and the St. Lawrence the thermal anomaly for January is — 18°, while it is + 30° between Iceland and Norway. In summer the anomaly for St. Mary’s is positive, but only slightly over a degree, the difference between the July means being 1.3°. The positive anomaly becomes greatest towards the interior of the continent, 157 MARYLAND GEOLOGICAL SURVEY ‘AJUNOD JAaATVD UT; *‘SHONUHUOD JOU IIB Sp10d0A BY} JO ISO ae — a | Wecmrioetesieg riietcte ste suOmo[og tee DELDOQOOSOO TRL FG 1 GT 49 To'6 |F8°6 | OOTE | TSIE |e | ees oF TH Jen-@| Le°z| Tre] 90°e | cee QP°P | G8°G | 18°E | 99°S | 6L°E/69°S/ EBS tls eee ee eee ees KIRA “Ig eee ss spjay faa terres TIBET aqqopRYD :£9UN0d 9} 10J sadvIIAy G86 FES | SLIT | F8°6 | 18°0/88°L | 90°6g | 98's) TFs! 6O'E| FOS 99° | E8°F| 96° | GE | ETS | 66'E | G9"E| 18%! FL | GOBT-ZEsT Son aeeetaaed SCLOLLOTOR ¥6°6 |S8TL |S | FLT |96°0 Gt'er | 69°LF | gee] FFE! LO°G| LEB! Fe°9 9° | GUS) AGF | €o'F | 16°F | 90°F) GQ°G] L | GLSI-TLST |oets ss eet soostaT “3g 48°6 |8T°6 | ST°VL |GET | 1Z°0| 86°FT | e9"EF | Te°s| eg'e | BL°% TO’ | 96°9 | T9°E| LTS | €0'F| 90°F | 96"F | TFG GG-e| L | OLBT-T9ST Jeret cere eee eee ss AIBA IS nae: 0 ov70 Tift fossese] sevest eves | sees! see leq-g! ta:#/ 41-91 ep-9 | gore leece| <=" | ape ze-z| | eer Pet eere sees eeeees O1TOgT-OJdOg wep eee eeerey esses"! 00°0) 280 | 94°98 182°L| OFF) ELT 69'T | Ta" 1) 96°2| $9°S | F6°g | 09'S] TFS] 89°E| OG 'T! Z GO8L-BB8T |e UMOUpLBUOAT Tes | 66°6 “GL /99°OL | 6470} 99°8 | Ga"OF | @o°z/ Ea'g | e8°G| ez-z! gee | ¥0°9| B9-% 96°F | 86'S | GFE | S9°S) FL°S| & | BEST-SEsT sess s Spray Adon T1'8 /S1°8 | 19°6 | 96°0T | 18°0/80°L | 62°98 |eE-z|ag1 99° 19°) 69°@ 60°F | 68°G | 8E°E | 98°E | COE | 9G"E | SI'S) 6 | SOBI-Z68T | “see TTRET aI40JaRNO 2 mn nm > mn a}au | Bee be leelee | gele is he |g le bes Weilses e-(os (etlee s/e | |e BRIBE / 2 (8lsiSleisi/siF/Sie/8/¢| 2.188 3 5 8 & g° Ss g g g s g fs |i\50 5 eS & | 8 |zs| ‘saex “suoTyRIg aE ea\es St SES] lee ey St] Bel Sinlioee a 4 8g 8 a Pr “KINDOD S,AUVIV “LS ‘VIV NOILVLlalodug TIA AIAVL 158 THE CLIMATE OF ST. MARY’S COUNTY reaching +18° in Arizona and Southern California. It is — 10° between the coast of Labrador and Greenland. The line of no departure les not far east of the Atlantic coast both in summer and in winter. PRECIPITATION. Table VIII gives the monthly and annual precipitation for all stations in St. Mary’s County. A critical examination of the material will lead to the conclusion that the annual average at St. Inigoes is above the true normal for the region; the total amount for the year 1872, which is 88.51 inches, is so much larger than the amount recorded anywhere else in the State that it should not be used. The period covered by this record (1871 to 1879) is too short to establish a normal record, moreover it is known to have been one with excessive rainfall, especially the years 1873, 1876, and 1879. The precipitation at Charlotte Hall appears too low, though it is known that there has been a rather marked deficiency in precipitation during the past 15 years in the eastern portion of the United States. St. Mary’s County receives annually slightly over 41 inches of rain- fall. The greatest average occurs in July, with 4.45 inches, which is 11 per cent of the annual total, and the least falls in December, with 2.79 inches, which is 6 per cent of the annual amount. The precipitation is small and nearly equal in amount during January, June, and Novem- ber. The uniformity in the distribution of rainfall is thus notable. Tables IX, X, XI, XII, XIII, and XVI contain the monthly and annual precipitation at all stations. TABLE IX. PRECIPITATION AT CHERRYFIDLDS, 1893-1899. alu Year. > SP wl ors ° o |] aA 2|)/A|< antes 27 | 3.34 eae 2. 38 | 2.85 | 34.17 25 46 1.93 38.45 1.2 28 | 1.40 | 37.21 a5 72 | 2.78 | 38.28 iy 29 | 2.83 | 43.38 9 CACY Hi palpnael hocedelli. | beudaclaaodar bocded|bbcdcdloocade| boobodlbenasa Jeveeeeleeeees tw - Means.. .-. 3.83 | 3.23 2.52 | 40.25 159 MARYLAND GEOLOGICAL SURVEY TABLE X. PRECIPITATION AT PORTO BELLO, Mp. ‘[enuuy “ABIL "Tady “Wore ter Year. WSOB eens ecauseriene TABLE XI. MONTHLY PRECIPITATION AT LEO Mp. NARDTOWN, "‘|epnuay Year. be: Q: Rotasi |i eaellncdsee SliOWTAN ieaaee 2 ra eee 2.64 10.8 ” seeee| 3695 | 4:08)| 6108 |..c...[s.0.5 46 6.17 2.78 | 8.95 [4.30 ||, vie) 1.80 | 4.40 ig we 4.38 | 1.21 2.29 | 1.13 | 5.31 TABLE XII. PRECIPITATION AT St. MAry’s, Mp., 1861-1871. | ss | ‘yenuuy | & | | ot oe Sc || 33 AON || sd ok NB 400 ae cicicirios : +S 7 | sini : = 10 92 ‘qdag REARS SO So | me = WARIS oo || oo = oa ae ; | morrow: 1D || Ot ‘sny Stoo Tes ses | GAY saisidnd 5 || xo | - : La RQraws ss go | Ane Oe inant seers etd O00 : co CHNRO * |] wo aunt (AG Suas? 6 i) Soh cased ek seo 44 od Cao os. ow “Aww | SSERABS te: ee Hs ores tas 15 ot OMNSen19G1010 : || gw ‘Tady SHBSASSL 38 cS 2 Gomes on 1D O> te ic ns “OIRI Cass eS :5SS CCS Cod HOS SSeoH so = ee ee — eee OE | tafe | ‘ i] rid + oa © | eo Moth § BaARBA B88 | IN er Mada fats cies |} 14 QO > :omanor moar TB GIs |) oe Se Seis emceinee eae Se Had | its : | 14 5 2 Poa . | C sm 4 3 i Se : | “) Z| So 2 - || pg H : || Qe cal o SOLER aB eaten ehenen Ba tteteall actin mc 1D OiI- DROS Oa BESESSeeeee & || FS ) OO RRR | Om 160 THE CLIMATE OF ST. MARY’S COUNTY Excessive precipitation (10.00 inches or more in one month) does not occur frequently in St. Mary’s County. Omitting the doubtful record of 1872 for St. Inigoes, it appears that the following large amounts have been recorded: Leonardtown, 10.32 inches, July, 1891; St. Mary’s City, 10.87 inches, in March, 1867, and 14.98 inches in August, 1861; St. Inigoes, 15.15 inches in August, 1873, 12.95 inches in April, 1874, and 11.01 inches in August, 1875. At all stations amounts less than 1.00 inch frequently occur. The lowest record for each station is: Charlotte TABLE XIII. PRECIPITATION AT St. INIGOES, Mp., 1871-1879. | | | i) | | | | o a $ . . g ia BO. eal es Sela 4s 5 ° ° a) Ss eilési}\45 0 66 1898 .. 2 10 il 13 10 45 | 1898. 2 12 23 18 23 12 8 98 1899 ... Bie ligesoud eeaccnl| 7 PAS Hp egac! 1899 . 2 16. || aide 25 22 ®) SoS 1900 .. 6 | Gry | sicrayeraie Ie lanqood 1900 1 9 WE lls eno 19 | 18 3 |: Spo IL DSS AU | nsh6ad Baadadboodad 1901 1 20 PA Nsanoen 23 11 UW Vesa E Means} 4 | 8 | 9| 9] 7 | 87 | Means} 2 | 11 | 20 | 23 | 2 | 12 | 3 | | f | =e hardly vary a tenth of a degree (Hann). On clear, cold nights the temperature at 5 feet elevation may. be from 5° to 10° lower than it is at 80 feet. The minimum temperatures in winter are lower at co- operative stations than would appear to be correct if comparison be made with the temperatures recorded at Baltimore. During the past few years the range of extremes at Charlotte Hall, in common with most other stations in Maryland has been quite remark- able. The summer of 1900 was one of extraordinary warmth throughout the eastern United States, while the preceding February (1899) was extremely cold. During the warm wave of August, 1900, the maximum at Charlotte Hall reached 102°, on the 11th; while during the cold wave of February, 1899, the lowest temperature was 19° below zero, the ground being covered with snow. During this cold wave the lowest tem- MARYLAND GEOLOGICAL SURVEY 169 perature recorded in the history of the Baltimore station occurred on the 10th, 7° below zero. On this occasion there was consequently an inversion of temperature (a rise of temperature with elevation instead of the normal fall) showing that the cold air occupied a relatively thin layer near the ground. Maximum temperatures above 100° are not very frequently observed at Charlotte Hall, though this figure was reached once in June and once in July, 1893, also in July, 1898, 1900, 1902, and in 7 | VI FEE | / y | [SS a a [a i | ei a oa Su Sceuend cera S005 CHENSERAN Fic. 10.—The warm wave of August, 1900, at—(a) Charlotte Hall, (b) Grants- ville, (c) New Market. September, 1900. Temperatures below zero were also experienced in February, 1895 (5° below zero on the 6th), and in January, 1899 (1° below zero on the 2d). Duration of Warm Waves. The maximum temperature exceeds 90° on the average 37 times per annum at Charlotte Hall; at Solomons only 20 times, showing the in- fluence of the inland location of the former station. The record of maximum temperatures is somewhat broken, so that the following table of dates, on which the maximum was 95° or above, is not complete. 12 170 THE CLIMATE OF ST. MARY’S COUNTY Dates on which the temperature was 95° or above at Charlotte Hall: 1893.—June 4, 5, 10, 19, 20, 25;* July 2, 8, 12, 18, 14, 15, 26, 30; August 25. 1894.—June 23, 24, 25; July 12, 13, 14, 19, 20, 26, 27, 29; August 9; Septem- ber 9, 10. 1895.—May 31; June;? August 9, 10, 11, 12, 15, 16, 24, 28, 29, 30; September 12; 19, 20; 21, 22, 23. 1896.—May 9,18, 19; July 27; August 5, 6, 7, 8, 9, 10, 11, 12, 13. 1897.—None. 1898.— June 12, 25, 26, 28; July 1, 2, 3, 4, 18, 19, 20, 29, 30; August 1, 2, 3, 4, 7, 8, 28, 31; September 1, 2, 3, 4, 5, 6, 7, 18. 1899.—June;* July;* August 5, 20, 21; September 6. 1900.—May 15; June 3, 4, 5, 6, 7, 8, 15, 16, 17, 18, 19; August 6, 7, 8, 9, 10, Ad, 12, 13, 14, 26, 2752 September’ 15 5: 16:)7,8).9;, 10) ads 1901 to 19042 * Record incomplete. The actual record for the August, 1900, “hot wave,” 6th to 14th, is represented in comparison with other stations in Fig. 10. The tempera- tures recorded were: 6th, 96°; 7th, 98°; Sth, 97°; 9th, 96°; 10th, 99°; 11th, 102°; 12th, 101°; 13th, 96°; 14th, 95°. The September record was also rather remarkable, viz.: September 5th, 95°; 6th, 96°; 7th, 100°; Sth, 98°; 9th, 95°; 10th, 96°, 11th, 99°. Duration of Cold Periods. The minimum temperature at Charlotte Hall falls below the freezing point of water on the average 92 times in the year, as compared with 68 times at Solomons. During the cold winter of 1895 it was below freezing 106 times. The average number of times with a minimum below 32° is 20 days in December, 23 in January, and 21 in February. The frequency of freezing temperatures in April and October is also slightly higher than for other portions of the county. The following record of the dates on which the minimum temperature was below 20° is also somewhat incomplete. Days on which minimum temperature was below 20° at Charlotte Hall: 1893..—December 2, 3, 5, 14, 21. 1894.— January 13, 28; February 2, 5, 6, 17, 24, 25, 28; March 27, 28; Novem- ber 29; December 28, 29, 30. 1895.— January 1, 2, 5, 13, 14, 20, 24, 25, 30; February 1, 3, 4, 5, 6, 7, 8, 9, 10, 41, 12, 13, 14, 17, 18, 23, 24; December 4, 6, 12, 13, 14, 15, 16, 17. 1Indicated record incomplete. MARYLAND GEOLOGICAL SURVEY aval 1896.—January 2, 4, 5, 6, 7, 11, 12, 15, 16; February 17, 18, 19, 20, 21, 22, 26: March 13, 14, 25; December 3, 4, 5, 22, 28, 24, 30. 1897.—January 7, 8, 9, 13, 25, 26, 27, 28, 29, 30, 81; February 1, 28; December 24) 25. 1898.—January 2, 4; February 1, 2, 3, 4, 5, 7, 17, 26, 27; December 2, 8, 9, 10, TPA gies, alk alby aly: 1899. January 1, 2, 3, 8, 11, 19, 20, 27, 28, 29, 30, 31; February 1, 2, 3, 8, 9, 10, 11, 12, 18, 14, 15, 25; March 6, 8, 9; December 7, 17, 21, 26. Feb-3 4+ 5 ODF EGY PIE ie) ee Pe faulty im COC Wi J] gee ia | jahate tH oT Cho | ae ! | 1 SERIE ! I TT CECH HH +H PAE 15| Err eoeo | is aan88 | { i | aint t t rol Cet HH Co / T a | HH if | } Bi l y tt = ++b ANI Pay | if T t to) -- +t . i ! | il i ne falafel BE ia = 1 aA -/0) : L ane aon | + | - | 2 | im! HH i ace ! | Fic. 11—Minimum temperatures during the cold waves of February, 1895, and 1899, at—(a) Charlotte Hall, (b) Deer Park. 1900.—January?* 2, 3, 27, 29, 31; February 1, 2, 3, 18, 19, 20, 25, 26, 27, 28; March 12, 13, 17, 18, 22; December 11, 12, 14, 15, 16, 17, ai, 22: 28, 29. 1901—January* 3, 4, 5, 6, 13, 18, 19, 20; February 1, 2, 6, 7, 8, 11, 12, 13, 14, 19, 20, 21, 23, 25, 28; March 6; November 20, 21, 22, 28, 29; Decem- ber to mois 6; tb, 16, 17.08, 19) 20, 21 9D 1902.— January * 7, 13, 14, 15, 17, 19, 20, 27. 28, 29, 30, 31; February‘ 3, 4, 5, 6, 8, 9, 11, 12, 18, 14, 15, 19, 20; December. 1903.4 1904.*—January* 3, 4, 5, 6, 8, 10, 12, 15, 18, 19, 20; February;? March 5, 29. *Record incomplete. 172 THE CLIMATE OF ST. MARY’S COUNTY The longest consecutive period of cold weather occurred in February, 1895; during that month the temperature was 32° or below on 25 days, and 20° or below from the 3d to 15th, as follows: 3d, 6°; 4th, 14°; 5th, 5°; 6th, — 5°; 7th, 8°; Sth, 1°; 9th, 5°; 10th, 10%: With, 93 12th, 10s 1th So tethe das sths tee, “hel tollow= ing is the record for the cold wave of February, 1899 (temperatures 20° or below) : 8th, — 1°; 9th — 16°; 10th, — 17°; 11th, — 19°; 12th, 4°; 13th, 5°; 14th, 4°; 15th, — 2°. These two remarkable cold waves are illustrated graphically in Fig. 11. Duration of the Crop Season. The date of the last killing frost in spring averages somewhat later than at Solomons, the mean for eight years being April 15; the average date of the first killing frost in autumn is October 17, 27 days earlier than at Solomons. While the record for Charlotte Hall is not very complete, the figures, nevertheless, indicate that the proximity of the waters of the Bay lengthens the growing season, which is 6 months and 2 days at Charlotte Hall, as compared with 6 months and 21 days at Solomons. A lght frost has occurred at Charlotte Hall as late as May 26 (1899), with a minimum temperature of 36°. The earliest light frost was apparently that of September 30, 1895. The following table gives the dates of the first and last killing frosts as far as available: KILLING Frosts. Last in Spring. First in Autumn, 18938 October 17. 1894 April 12. October 15. 1895 April 12. October 10. 1896 April 9. October 25. 1897 April 21. November 13. 1898 April 28. October 24. 1899 October PI 1900 April 15. October aly, 1901 April 5. October 16. 1902 October 30. 1903 October = 27. 1904 April 22. MARYLAND GEOLOGICAL SURVEY 173 PRECIPITATION. The exigencies of Prof. Coad’s private affairs necessitated his frequent absence from station, with the unfortunate result that the records of TABLE XNXI. MONTHLY AND ANNUAL PRECIPITATION AT CHARLOTTE HALL, Mp., 1892-1904. s = Year. 5 x | es 2 a ap rs > GEMS Alte | a | @ 3) fe 5 i || 5 z a ir) & A 4 = 45 5 < n is) a A < ae BiTGI ASA apc cel| Bee cesta | eke cae at ced eecea| Sete a OSes [esceee), 1-06 |[8.68/|)1248)|:cceee| 448 |<. ..0-( 2:61 [coe 3.46 | 0.91 | 3.10 |...... 1.15 | 2.91 | 2.79 | 2.04 | «.15 | 1.65 (fi Rerned 1.38 | 3.28 | 6.65 | 4.68 | 3.99 | 3.25 | 1.59 |...... | 2.65 | 2.20 | 1.97 | Bteistsie 4.87 | 3.82 | 1.03 | 1.16 4.38 | 2.82 | 0.94 |...... »- >| 1.08 | 0.34 |..... 5.03 | 2.52 | 2.33 | 4.69 | 2.69 | 6.78 | 3.04 | 0.95 | 6.21 | 3.19 | 2.98 | 42.16 1.10 | 4.33 | 3.42 | 4.98 | 1.76 | 4.27 | 4.00 | 1.69 | 2.96 | 2.40 | 2.73 | 36.94 5.75 : | -| 5-58 | 4.36 | 4.39 | 1.41 | 1.75 |...... 4.44 2.07 | 4.79 | 2.62 | 1.89 | 2.89 | 40.25 0.10 -98 | 1.53 | 4.10 }..... 3.19 Jeceeceleese ce) BBO |... ele sees lee eee eleoeeee| 4632 | eecees leeeee leweeee Laat 3.26 Greatestamount..| 4.15 | 5.75 4. Least amount..... 1.75 | 0.10 0. J Difference.........| 2.40 | 5.65 | 3.70 | 6. GREATEST PRECIPITATION IN 24 Hours aT CHARLOTTE HALL, Mb. d| 5 Year. & i) 8 z B ES |) fey | dep |) Edel ee Wh es : 3 a 3 Q 3 =] Cc c a SS gee Ree Wea eee SS ee Re I ee es ee A Sd oe eta (eaeee 0.52 | 1.80 | 0.58 |...... 2.02 |......| 070 |....-- 1.00 | 1.07'| 0.26 | 1.09 |...... 0.60 1 (0 | 8.00 | 3.00 1.02 | 0.50 | 1.40 | 3.67 | 1.12 :68 | 1.10 | 3.67 1.57 | 1.98 | 1-00 | 0.88 | 0-30 198 | 0.24 |...... 1.04 | 1.60 | 0.96 | 0.75 | 1.93 | '32 | 1.38 | 2.20 0.76 | 0.86 | 0.92 | 1.21 | 1.52 .69 | 0.80 | 1.98 1.16 | 3.00 | 0.96 |...... 1.00 86 | 0.90 | 3.00 1.13 | 1.60 | 0.50 | 2.15 | 0.68 00 | 1.95 | 2.72 2.10 | 0.10 | 0.80 | 2.50 0.95 6 | 1. Fee Br | LEON eee | 1.62 ; cross |lrcooedl! Beaod 2 0.67 | 1.50 | 0.76 j | am i ae | -10 | 3.00 | 1.40 | 3.67 | 1.93 | 2.56 | 2.72 | 1.74 2.40 | 2.20 | 1.36 | 3.00 | 3.67 1901 | 1899 | 1895 | 1895 | 1897 | 1900 | 1900 | 1898 | 1900 | 1807 1901 | 1894 | 1895 i213] 2 | 8 | 13 |iv-ts| 12 | 12 | 35 | | | | rainfall at the station are much broken, especially during the summer months. It is probable that the averages found are slightly too low even for the period covered; certainly the mean for August (2.69 inches for 8 months) is rather low. 174 THE CLIMATE OF ST. MARY’S COUNTY The precipitation for the interior of St. Mary’s County may be ex- pected to be somewhat smaller than the average for the county, and the record for Charlotte Hall may be accepted as fairly correct as a whole. The annual total for 9 years is 36.79 inches. The complete record for Solomons gives 39.05 inches. The station has not received a total of 10.00 during any month, the maximum record being 7.08 inches in April, 1901. Amounts less than 1.00 inch are not uncommon. The smallest total was 0.10 inch in February, 1901. TABLE XXIII. MONTHLY AND ANNUAL SNOWFALL (UNMELTED) AT CHARLOTTE HALL, MD. a . = year. e art psoas ll Mh tha BS. |p Wes | es Saalese is ar Salou lis Bs 5 13 BI Ss | © ° o q rd ical re) 4 a 5 bar] <4 n ° A A 4 6 | 01 || oil “o| (0 |, oni) 0) | Moulh lay earon ite 1865) Den (Ole 2008 O)e OM) On RON a etO ela TanMS!> me BIe 0) EDV |/270) 1/001" 1/8 0/8) | CON Ine tOin|l| Oy mtn Opal 0863) 12 Oem seb, 7.0} 0} O O |) @ 0 OO Or On, Oa Bee aes OW OO Ge Wet AO We PO) eeahl! aes Try 89.5 6.0; 0 | 0 | O } OF) O } OF | O | OO} fOr B1L0 820i Fic. Zz SHOWING GROWTH OF I.—VIEW Fic. > | us “ee tC ADEs Ce ny pn a” =e 7 € , ue + a a aon Bi) Me ‘ in : a. : ii i - - : ce =) ae : at ae Tt et eve a ty ei eg 7 sit ¥ Toe i one a= Mee ies Geriig, Fie we 2k aie ae a a5 = eS vA eas eae ch, elie > . ae ie Bs a ae > —aba< +s ww _ a ee a — q ce ee eve ey Pe: aon Rare tot ce: SS ie . ee3 ane ore ot Ssh MARYLAND GEOLOGICAL SURVEY 193 SAWMILLS AND THEIR Propucts.—There are about twenty-two saw- mills cutting timber in St. Mary’s County. The amount cut by each mill ranges from 25,000 to 1,500,000 board feet annually. These mills are scattered throughout the county, and have a combined annual cut of 7,075,000 board feet. The bulk of the timber cut in these mills is pine, oaks, yellow poplar, and red gum. Of these only the best grades are shipped out of the county. In the southern part of the county about two-thirds of the timber cut is pine and one-third hardwood, while in the northern part this propor- tion is about one-third of pine to two-thirds of hardwood. On an average for the whole county, about one-half is pine and one-half hard- woods. A good deal of the best grades of pine and white oaks are sawn into construction timber and shipped out of the county, while the remainder is cut into boards, planks, and dimension stuffs for local use. Occasionally red gum is sawn for outside shipments, but until recently the market price of this timber has been so low that the mill men could not cut it profitably. Red gum is now bought largely for the manu- facture of fruit baskets. It is also used locally for construction timber and for such less important purposes as staves for tobacco hogsheads, boards for fencing, and for shingles. Of the entire amount of timber cut into lumber, only about 1,500,000 board feet are shipped out of the county. This leaves approximately 6,000,000 board feet for local consumption. With a population of nearly 16,000, this allows a consumption of 370 board feet per capita. The average consumption per capita in the United States is being placed at 510° board feet. Corpwoop.—The supply of firewood in St. Mary’s County is a simple problem. Firewood is abundant and the cost per cord on the market is determined largely by the cost of cutting and hauling. The best quality of hardwood can be bought on the stump for less than 50 cents per cord in almost any locality, while scrub pine sells for 25 cents or less. It is estimated that approximately 2000 cords of firewood are 1Forest Economics, B. E. Fernow. 194 THE FORESTS OF ST. MARY’S COUNTY shipped out of the county every year. It goes principally to Baltimore and Washington. Hardwood brings $2.50 per cord at the wharf, and pine $2.00. From the data gathered within the county it is estimated that the 4000 families in St. Mary’s County use approximately 55,000 cords of wood annually, or an average of 14 cords per year for each family. Eleven cords can be cut on an average from an acre of forest land, so that the annual consumption of firewood in the county represents a stand of timber of about 5200 acres. On the 105,960 acres of forested land there is now standing approximately 1,165,560 cords of wood, counting 11 cords to an acre. This includes all standing timber over 4 inches in diameter on the stump. At the present rate of consumption it would require about twenty-one years for all the wood to be consumed in the county in the form of cordwood alone, not counting the annual increment of the forest in the meantime. The volume of this yearly increment of the forest is estimated to about balance the total consump- tion, though the kind and quality of the timber is constantly deteriorating under the present lack of proper conservative management. Rartway Tins.—The forests of St. Mary’s County have long been an important source for ties and other railroad construction timber. The supply for these purposes is now, however, almost exhausted. Formerly several hundred thousand ties were cut and shipped annually, but during the last two years the shipments were less than 50,000 ties and hardly any bridge timber. Up to the last year (1904) the railroad companies accepted all kinds of oak and chestnut ties produced by the county, but at the present time (1905) they desire only white oak and chestnut. This will materially diminish the future cut of ties in the county. Moreover, owners of timber are somewhat reluctant to sell white oak to contractors who will not at the same time accept red and black oak timber. The Spanish, red, yellow, and other black oaks are considered inferior grades by railroad companies, and experience has proved to them that the life of a tie cut from one of these oaks is only a little more than half that of a white oak tie. Contractors realize from 60 to 70 cents MARYLAND GEOLOGICAL SURVEY 195 for their white oak ties, depending upon the grade of tie. Chestnut ties range from 45 to 55 cents, delivered at the railroad. Two classes or grades of ties are distinguished by contractors and railroad companies. The first class includes ties which have a face of 8 inches or over and are free from all defects, such as knots and checks. Second class ties may have some knots and a face of not less than 7 inches. All oak ties must be hewn. Chestnut ties are cut largely from old mature trees, and are cut into their required dimensions in the sawmill. Contractors hire choppers who cut ties at the rate of 10 cents for the best grade and 8 cents for the second grade. Punpwoop.—Yellow poplar and scrub pine are cut extensively for the manufacture of wood pulp. The latter is used in excess of the former solely because it is more abundant in the county. Experienced dealers in the county estimate that about four thousand cords of pulpwood are shipped annually out of the county. About one-fifth of this amount is yellow poplar. Scrub pine, being much more abundant, is the staple timber for this purpose, and consumers of pulpwood have no difficulty in buying large tracts of it at very low prices. Stumpage prices of pine vary according to the distance from railroad or wharf, and also according to the age and density of stand. The different items making up the price per cord of scrub pine for pulpwood vary as follows: SUUMIPAL Cae jevefecsvere ste sueseleroiaveteycce reve tsseucTere reverent eis eave arsiaveasie $ .20 to $ .25 GU b IT Sa erciperetenstotare sectsicrs Ghevencce Neysteretae nek oh Vo sreraual Saree Sika ees apy Ss ale:K) ISIN bIbb AYE? cae cierom cree or cls aio Un Metra Orc Onion ence 13 Oe eb O PROGA CM cys eyese ois rei srekavoverenetel areveneice, ove wise WiavcrareChn's! ste vyaveus avi $2.75 “ $3.15 The scrub pine is cut during the spring and summer seasons when the bark can be taken off most easily. All trees above 4 inches in diameter a foot above the ground are cut into 5-foot lengths. A saw is used so as to insure uniform lengths and facilitates in loading on cars or boats. Scrub pine has only lately come into favor for pulpwood, and it is believed that the demand for this species will increase. Loblolly pine is not cut for pulpwood. 196 THE FORESTS OF ST. MARY’S COUNTY Owing to the scarcity of yellow poplar it is difficult to secure tracts from which this timber can be cut profitably. On an average, 2 cords may be expected from one acre of land where the soil is suitable for this species. Tracts yielding less than this are seldom worked for pulp- wood because of the inconvenience of getting it out of the forest. Stumpage prices are usually high, and the trees are so widely scattered that it hardly pays to cut them. The following items show the first cost of a cord of yellow poplar pulpwood: Savior 284-1 GOES OURO POCO OS OOdU DOOR UOT ONDAUOO cate $ .90 to $1.10 (Giliahdt-de ner Os eCHeG oc Hono pectbocuood onoopasquouraE abe) SS ah) isk Whi AagagsouaooopeddoUcDocenoduoDotoooodoNooEoed aby) 92 aN) UNE MAM tOUDUpOTOabS TaMoOOOS AD UOUS CoOL OD DADauOS $3.70 “ $4.30 Contractors’ prices to consumers are generally from $4.50 to $4.75 per cord, delivered at the landing. VeNeERS.—The manufacture of red gum veneer for fruit baskets is constantly increasing, and the supplying of timber for this purpose has become a staple industry in St. Mary’s County. Red gum timber can be bought from owners for 50 cents per cord on the stump. The cost of cutting and hauling is the same as that of yellow poplar, making the total cost for one cord of red gum at the wharf about $3.50. The market price is about $4.00 per cord containing 173.33 cubic feet. Sticks are cut 5 feet long with the bark removed. The cord measures 8 feet long and 5 feet wide, by 4 feet and 4 inches in height. TELEGRAPH PoLEs aND Pitres.—The available timber in this county desirable for piles, telegraph and telephone poles is white oak, chestnut, and loblolly pine. The demand and consumption of chestnut and white oak ties has been so great, however, that very few poles and piles have been cut from these species. Contractors for supplies of pole and pile timber from this county are, therefore, largely restricted to loblolly pine. Formerly, this pine could be bought rather cheaply in the southern part of the county, but of late the price, owing to the demand for other purposes, or for lumber, has increased so enormously as to prohibit the purchase of this timber for piles and poles. Large areas of old fields MARYLAND GEOLOGICAL SURVEY 197 which have come up to loblolly pine are now furnishing material more valuable for lumber than any other purpose. It is believed that red, yellow, and black oak will find a place on the market for piles, since they are no longer accepted for railroad ties, especially if preservative treatment is resorted to. These oaks are never used for poles, but are constantly used locally for piling in the con- struction of private wharfs. Fence TIMBer AND StTaves.—Red juniper is the principal species used for fence posts, and is noted for its lasting qualities in contact with the soil. Sawmill men handle these posts at $20 per hundred, though none are shipped out of the county. Boards for fence material are largely cut from scrub and loblolly pines, and are quoted on the local markets at $11 per thousand board feet. Clapboards are cut from red gum, red oak, scrub pine, and loblolly pine. Formerly a large number of fence rails and posts were cut from chestnut, but since this timber is becoming rather scarce in this county farmers resort to red and black oaks, scrub pine, and loblolly pine. Staves for tobacco hogsheads are cut largely from scrub pine. Occa- sionally loblolly pine and red gum are used. These staves are sold by all sawmill men in the county and are 5 feet 4 inches long, and from 3 to 6 inches wide. They are quoted on the market at $8 per thousand board feet. DerstRUCTIVE INFLUENCES. Forest Fires.—The forests of this county have been remarkably free from destructive fires. There is no record of a fire having occurred within the county which caused any severe damage to the forests. The numerous streams of the county serve as natural firebreaks, being nearly at right angles to the prevailing winds. These streams are usually bor- dered by wet or damp soil and dense vegetation, which is scarcely ever in condition to burn readily, and furnish impassable barriers to any ordinary fire. The county is also so thoroughly cut up by areas cleared for farm purposes that they, with the numerous wagon-roads throughout 198 THE FORESTS OF ST. MARY’S COUNTY the county, serve as additional fire-lines. Even the little-used wagon- roads are usually gullied by erosion and devoid of vegetation. On the other hand, the people of the county are notably very cautious in regard to fires, and as there are no very large tracts of forests not immediately under the care of the owner himself, or someone directly responsible, fires are not left to run on until they cannot be easily put out. The immediate danger to which numerous small dwellings or cabins scattered throughout the forests are subjected likewise tends to make the inhabitants careful regarding forest fires. The prevailing forest types, being of mixed hardwoods, are not especially subject to destructive fires since the forest floor is usually moist and in places even wet. On the higher elevations where the scrub pine predominates, and on the lower level sandy parts, where the loblolly is found, the soil is covered with a thin layer of needles which is not sufficient to feed a destructive fire. The danger of fire from locomotives is very small, since there are less than ten miles of steam railway in St. Mary’s County. Charcoal burning, which is a fruitful source of fires in neighboring counties, is not carried on here, and as this county is almost surrounded by water the ability of fire entering from adjoining localities is practically eliminated. Grazine.—This county is not well adapted to grazing. There is not enough of it carried on to damage forest reproduction. On account of insufficient fodder supply for winter use, very few cattle are kept by the farmers. Along the streams and wet places the growth consists of shrubs and trees, with very little grass, while on the cleared farming land the soil is so loose and sandy that cattle would soon trample the meadow grass into the sand and ruin the pasture. A greater source of damage to the forests of St. Mary’s County is that afforded by herds of swine which feed in the forest. During the fall and early part of the winter, they subsist on mast, but in spring and summer they dig up the forest soil in search of roots. The young growths are killed and the mature trees are seriously injured. Fre- quently, even large trees are killed outright. In their search for the soft inner bark of the oaks, chestnut, and pine, hogs remove the bark of MARYLAND GEOLOGICAL SURVEY 199 the lower part of the trunks as well as that of the roots, so far as they are able to dig them up. OrueEr Destructive INFLUENCES.—The following are also destructive to the forests of this region: injudicious cutting; clearing Jand better suited for forest growth; and erosion. Injudicious cutting of the timber has been going on in this county since its settlement. Nearly all of the areas have been cut over many times for the purpose of securing certain timber species for special pur- poses. This constant stripping the forest of its most valuable timber has left not only too few and poor, immature trees as the only repre- sentatives of the more valuable species, but it has also permitted the less valuable species to become too abundant. As a direct consequence large tracts of forests now present a very irregular and uneyen-aged appearance, with very few good timber trees remaining. The woodland owners of St. Mary’s County do not fully realize the decline of their forest resources. When wood is needed but little discretion is exercised in the choice of trees to be cut, and no provision is made for the renewal or improvement of the stand. Large areas throughout the sandy and rather unproductive regions of the county were stripped of their timber, and cultivated for farm crops for several years. When they ceased to yield a crop sufficient to pay for the tilling of the soil, they were abandoned and allowed to revert to nature. A scrubby growth of oaks, black gums, persimmon, and scrub pine now occupies these old farms. Frequently, such areas have come up to a pure stand of scrub pine which forms about 10 per cent of the forests of the northern half of the county. Formerly, the entire county was covered with a dense stand of hardwood timber with oaks, chestnut, and hickory predominating. The lands now occupied by the better forests are those which have never been cleared. These are narrow strips along the streams and Bay shores. In the central part of the county the surface is rather undulating, especially along the streams. The earlier settlers cleared the land at the foot of the hills; the later settlers enlarged the fields by taking the timber from the hillsides. The loose, sandy soil on these cleared slopes 200 THE FORESTS OF ST. MARY’S COUNTY was soon washed down into the valley below, which rendered eroded areas unfit for further cultivation. (See Plate VIII). The more valu- able bottom land along the streams is being covered with sand and gravel, washed there from higher places. Natural tree reproduction on such eroded hillsides is very tardy. Scrub pine is the only tree which will reclaim such areas. Farmers are, however, very cautious about such clearing at the present time, and seldom clear any land which is liable to erode. FUTURE OF THE FOREST UNDER JUpICIOUS MANAGEMENT. St. Mary’s County dealers in lumber and railroad ties are very eager to see both public and private interest taken in the preservation of their forests, and particularly in the young growth. They realize that some systematic management should be instituted if reasonable returns are to be expected in the future from the timbered areas. Farmers and owners of timber tracts realize that the woodlands are constantly depre- ciating in value in spite of the greater demand for forest produce. The best timber having been cut, the farmer is eager to find a market for the less valuable species. Every farmer owns some forest land from which he draws his fuel supply, fence material, and saw logs for build- ing purposes. Frequently, ties, poles, and piles are cut during the winter to secure some income from the woodlot to pay taxes and other expenses, but usually very little care is taken as to where and how the trees to be cut are selected. Woodland owners can enhance the value of their timber considerably by making what is generally termed improvement cutting instead of chopping down trees indiscriminately. Improvement cuttings can be carried on in all woodlots in this county with excellent results by remov- ing overmature trees, and by thinning out’ undesirable species where they interfere with the growth or reproduction of more valuable kinds. Such a cutting gives the remaining trees enough room and light for their better development. There are numerous overmature and diseased chestnut, oaks, and red gum trees which are injuring the younger growth about them. These should be removed gradually as the material can MARYLAND GEOLOGICAL SURVEY. ST. MARY'S COUNTY, PLATE XVI. Fic. 2—vIEw SHOWING METHOD OF TRANSPORTATION OF LOBLOLLY LOGS TO THE MILL. Nabi : vee, oh i. 4 ye = a ee mas Lae leo at ae PUR ons S&S bdé 7 i> a . 7 ak =) ay MARYLAND GEOLOGICAL SURVEY 201 be utilized. In mixed hardwood forests, the selection system of cutting should be put in operation. The principal of the selection method is that the trees should be selected and cut here and there in the forest according to the owner’s purpose. In this method trees may be removed from year to year as they reach a required diameter, and the wood from the top of those trees in addition to that which results from the cutting of inferior species and diseased trees will yield fuel supply for the owner. For the production of telegraph poles and railroad ties the trees may be cut as soon as they reach the desired diameter, and for wood for construction purposes, considerable thinning must be made so as to give the larger trees sufficient ight and growing space. In this way the forest is opened rather uniformly and at the same time sufficiently to permit the reproduction of desirable species. In forests composed mainly of oaks and chestnut, which sprout well from the stump, it may be advisable to cut most of the good-sized trees over a part of the tract for the purpose of raising a crop of sprouts. Stumps should be cut low and slanting, so as to prevent rotting and secure strong and numerous shoots. Trees from seeds are, however, more desirable than those from sprouts if large timber is the object. Sprouts are frequently defective at the butt. The pine forests are invariably even-aged and seldom need any further attention beyond that of protection from fire, which has thus far been no great source of damage in this county. The stand of pine necessarily needs to be rather dense, so that the lower part of the trunk will shed its branches early from want of sufficient light. In harvesting a growth of pine clear cutting is recommended with from 3 to 5 seed trees left distributed as uniformly as possible over every acre, if the area is again expected to grow up to pine. When broad-leaf trees are desired on such cleared areas, planting is advised. Acorns of red and white oaks may be planted four by four feet apart. Acorns for this purpose must be collected in early fall and put in boxes with alternate layers of sand. The boxes containing the acorns must be kept in a moist, cool place over winter. They may be buried in the earth about a foot below the 14 202 THE FORESTS OF ST. MARY’S COUNTY surface of a well-drained hillside. In early spring, the acorns should be planted in hills. It is preferable to plant three acorns to a hill. The brush left after cutting may be burned where this is possible without injuring the trees left in the forest and at a season when there will be little langer of the fire spreading. Where this is not practicable, it should be scattered out over the forest floor so as not to be a hindrance to reproduction. The whole aim in forest management is to secure new trees of the most useful kind to take the place of those cut out as soon as possible after the removal of the old. For the best results it is essential that fire and grazing animals be kept out of woodlots. Fire running over the forest soil consumes the litter and kills the seedling and sprouts and reduces the vitality of old trees and frequently kills them outright. By the removal of the litter the forest soil is exposed and becomes too dry to encourage the germination of tree seeds. Grazing animals do consid- erable damage to woodlots and should be excluded. Cattle browse upon young growth and trample it down. Swine not only eat the nuts of the chestnut, oaks, and hickories, but they also dig up the forest soil and kill young seedlings and sprouts. Much damage to the young growth can be prevented if cuttings are made during the winter months, preferably when there is snow on the ground. Marking of trees may be done in the summertime when trees are in foliage, because at this time more accurate judgment can be exercised as to density of stand, condition, and health of trees. There is very little attention paid to the management of woodlots in St. Mary’s County. It is a simple preblem, however, and every farmer can regulate the cutting of the timber and improvement in such a manner that it will not prove a burden to him financially. Every farmer should fully realize that protection and selection of cutting are factors of prime importance in managing his woodlots to secure the highest financial returns. In case woodland owners desire a special and more detailed plan for the management of their woodlots, they should make application to the State Forester, Baltimore, Md. The demand for cordwood for home consumption is not likely to in- MARYLAND GEOLOGICAL SURVEY 203 crease in this county unless the proposed railroad should he opened and the population increased in the neighborhood of Point Lookout. It is believed, therefore, that it would not be profitable to manage a woodlot for the production of cordwood only, under present market conditions. SUMMARY. The following is a summary of the principal facts determined by a brief study of the forests of St. Mary’s County: 1. Almost one-half of the area of the county is covered with forests. 2. The most desirable timber has been cut. 3. Formerly, the forests consisted of hardwood species. 4. At present, 20 per cent of the forests of the county are scrub and loblolly pine, the pines tending to become the prevailing species. 5. The most valuable timber now standing is white oak, loblolly and scrub pines. 6. The hardwood forests are very uneven-aged and irregular in density of stand which renders lumbering difficult and unprofitable. tT. The white oak and chestnut which are the most valuable railway timbers are becoming scarce. 8. Yellow poplar and scrub pine are largely cut for pulpwood. 9. Red gum which was formerly of little use and importance is now in demand for lumber and the manufacture of veneer. 10. Fire and grazing which have retarded satisfactory reproduction have injured the mature timber of the county very little. 11. Forest land could be made fully profitable by carrying out the following recommendations: (a) Removing dead, dying, and_ over- mature trees. (b) Removing mature or inferior trees which are suppressing or hindering desirable young growth from coming up in the forest. (c) In case of excessive cutting leave at least from 3 to 5 seed trees to the acre. (d) Planting where desirable reproduction is not coming up reasonably soon after cutting. (e) Preventing fires and excluding grazing animals from areas where young growth is coming up. i + a ae a ipa Ae : i aa a a rs ue Beet) ey INDEX A Abbe, Cleveland, Afi a0) Agricultural conditions, discussed, 139. . Alexander, John H., 30, 41. Alexander map, 30. Alsop map, 27. Analyses of Leonardtown Loam, 129. of Meadow Land, 137. of Norfolk Loam, 127. of Norfolk Sand, 132. of Sassafras Loam, 133. of Sassafras Sandy Loam, 136. of Windsor Sand, 131. Areal distribution of Calvert formation, 69. of Choptank formation, 73. of Lafayette formation, 82. of St. Mary’s formation, 76. of Sunderland formation, 85. of Talbot formation, 93. of Wicomico formation, 91. Areas of soils, 126. Artesian wells, 123. Atkinson, Gordon T., 5. Babb, Cyrus C., 47. Bagge Hee. ait. Dill. Bailey, J. W., 43. Barry, J. Neilson, 153, 176. Bassler, R. §., Bauer, L. A., 18, 49, 51, 179. Baylor J. B., 180. Berry, I. W., 7. Bibbins, A., 7, 104. Bonstcel, Jay A., 17, 38, 50, 125. Boyer, C) Sz, ‘bil Building-stone, discussed, 118. Bushwood, artesian well at, 123. Cc Calvert Cliffs, 68, 70, 72, 73, 74. Calvert formation, 68. areal distribution of, 69. character of materials of, 71. stratigraphic relations of, 71. strike, dip, and thickness of, 70. sub-divisions of, 71. Calvert water-horizon, 124. Case, Dy G:) D1: Cecil county, coastal plain in, 56. Chancellor Point, section at, 80, Chaptico, artesian well at, 123, Chaptico creek, 177. drainage area of, 177. Character of materials of Calvert forma- tion, 71. of Choptank formation, 74. of Lafayette formation, b of St. Mary’s formation, 78. of Sunderland formation, 86. of Talbot formation, 95. of Wicomico formation, 92. Character and composition of forests, 184. Charlotte Hall, temperature conditions at, 164. precipitation at, 173. snowfall at, 174, 175. meteorological summary for, 162. Cherryfields, mean temperatures at, 153. precipitation at, 158. Chesapeake Group, 68. origin of materials of, 80. sedimentary record of, 98. Chestnut, 189. Choptank formation, 72. areal distribution of, 73. character of materials of, 74. stratigraphic relations of, 74. strike, dip, and thickness of, 73. sub-divisions of, 74. Clark, Wm. Bullock, 7, 9, 46, 47, 48, 49, 50, 51, 52. Clays, discussed, 113. Cleaveland, Parker, 32, 39. Clifton Mills, section at, 93. Climate, discussed, 147. Climatie data, 148. Climatology of Charlotte Hall, 161. Coad, J. Edwin, 148, 176. Coad, J. Francis, 149, 161, 176. Coastal plain in Maryland, 56. Columbia Group, 84. origin of materials of, 97. sedimentary record of, 99. Commercial trees, 188. Conrad, T. A., 34, 40, 41, 42, 48, 44, 45. Contents, 11. Cordwood, 193. Cornfield harbor, 105. artesian wells at, 124. Cuekold creek, section at, S80. Cultural treatment of forests, 200. 206 D Dall, W. H. 46, 47, 49, 52. Dana, J. D., 35, 45. Darton, N. H., 36, 37, 47, 48. Day Da 46: Desor, E., 44. Diatomaceous earth, discussed, 120. Drainage, 59. Drum Cliff, 74 section at, Ducatel, J. T., 29, 41, 42. Dug wells, discussed, 122. Duration of crop season, 172. Duration of warm waves, 169. Duration of cold periods, 170. E Eastman, C. R., 52. Economie resources, discussed, 113. Ellicott, James F., 148, 176. Eocene water-horizon, 123. Extremes of temperature at Charlotte Hall, 165. F Fairhaven diatomaceous earth, 71. Farrer map, 27. Fence timber, 197. Finch, John, 32, 34, 40. Tisher, R. S., 44. Forests, discussed, 183. Forest fires, 1 Forest types, 187 Iorest trees, 185. Fossils from southern Maryland, 33, 34. To! Fossils of the Choptank formation, 76, 79. of the Lafayette formation, 81. of the St. Mary’s formation, 78, 79, 80. of the Talbot formation, 103, 105. Future improvement of Forest lands, 200. G Geographic research in St. Mary's county, 26. Geologie research in St. Mary’s county, aul; Geology, discussed, 67. Gibbes, R. W., 43. Glenn, L. C., 52: Gravels, discussed, 118. Griffith, Dennis, 29. GioverseN. GC. c1S nlite H Harlan, R., 43. Harris, G. D., 48. INDEX Hay, O. P., 53. Hayden, H. H., 32, 39. Heilprin, Angelo, 35, 36, 45, 46. Herrman, Augustin, Herrman map, 28. Herrmann, C. F. von, 17, 147. Higgins, James, 44, 45. Historical review. Hollick, Arthur, Hoxton map, 29. Hyatt, Alpheus, 176. Hydrography, discussed, 177. Illustrations, List of, 15, Infusorial earth, 120. Interpretation of Geologic record, 98. Introduction, 21. J Johnson, A. N., 50. Jones Wharf, section at, 79. Joy, Geo. W., 176. Ee Lafayette formation, 81. age of, 81. areal distribution of, 82. character of materials of, 83. origin of materials of, 83. sedimentary record of, 98. stratigraphic relations of, 83. structure and thickness of, 82. Lafayette stage, 61. Langleys Bluff, section at, 96. Lea, Isaac, 34, 40. Leonardtown, artesian wells at, 124. magnetic station at, 179. mean temperatures at, 154. precipitation at, 159. section near, 90. Leonardtown Loam, 127. mechanical analyses of, 129. Lindenkohl, A., 47. Loblolly pine, 190. Local sections of Miocene age, 79. of Sunderland age, 90. of Talbot age, 95. of Wicomico age, 93. Lord Baltimore map, 27. Lueas, F. A., 53. Lyell, Sir Charles, 35, 43. M Maclure, William, 25, 32, 89. Maddox, artesian well near, 123. Magnetic declination, discussed, 179. Markoe, Francis, Jr., 43. Marls, discussed, 119. INDEX Martin, G. C., 52. Martenet map, 30. Maryland Geological Survey, 31, 87, 49, 50, 51. Mathews, FMdward B., 7, 49. McGee, W J, 37, 47. MeIntosh run, 178. drainage area of, 178. MeWilliams, Alexander, 148, 176. Meadow Land, 136. mechanical analyses of, 137. Mechanicsville, magnetie station at, 180. Meek, F. B., 45. Mell, C. D., 18, 183. Meridian line, 180. instructions for using, 180. Merrill, Geo. P., 49. Meteorological stations in county, 176. Meyer, Otto, 36. Millers Bo Uieai, lite ldls. Millstone, artesian well at, 124. Miocene, 68. local sections of, 79. origin of materials of, 80. water-horizon in, 123. Morton, 8. G., 34, 40. N Natural deposits, 113. Newton, R. Bullen, 51. Nomini Cliffs, 72. Norfolk Loam, 126. mechanical analyses of, 127. Norfolk Sand, 131. mechanical analyses of, 182. Nuttall, Thomas, 32. ie) Oakley, artesian wells at, 123. Origin of Lafayette materials, 83. of Miocene materials, 80. of Pleistocene materials, 97. Pp Patterson, H. J., 119. Pearson, artesian well at, 124. Physiography, discussed, 55, Piles, 196. Piney Point, artesian well at, 124. Pleistocene, S84. origin of materials of, 97. Pliocene, 81. Plum Point, 71. Porto Bello, mean temperatures at, 154. precipitation at, 159. Potomac river, section on, 96. Precipitation, discussed, 158. Precipitation at Charlotte Hall, 173. Preface, 17. Pulpwood, 195. Q Quaternary clays, discussed, 115. R Railway ties, 194. Rau, Chas., 46. Recent deposits, 96. Recent stage, 66. Red gum, b Red juniper, 191. Remsen, Ira, 5. Ridge, mean temperatures at, 153. Ries, Heinrich, 51. Robinson, Samuel, 40. Rogers, H. D., 43. Rogers, W. B., 34, 41, 43. SS) St. Clement river, 178. drainage area of, 178. section on, 90. St. George’s island, artesian wells on, 124. St. Inigoes, artesian wells near, 124. mean temperatures at, 155. precipitation at, 160. St. Mary’s, mean temperatures at, 154. precipitation at, 159. St. Mary’s County, agricultural condi- tions in, 139. artesian wells in, 123. building-stone of, 118. clays of, 113. climate of, 147. diatomaceous earth of, 120, drainage of, 59. dug wells in, 122. economic resources of, 113. forests of, 183. geology of, 67. gravels of, 118. hydrography of, 177. magnetic declination in, 179. marls of, 119. meteorological stations in, 176. miocene in, 68. physiography of, 55. pleistocene in, 84. pliocene in, 81. precipitation in, 158. recent deposits of, 96. sands of, 11T. soils of, 125. soil types in, 126. springs in, 121. structure of coastal plain in, 61. table of precipitation in, 157. table of temperatures in, 152. temperature conditions in, 151. 205 INDEX thermal anomalies in, 1% topographic description of, 5 topographic history of, 61. transportation facilities in, 23, 144, 192. water resources of, 121. wood consumption in, 192. St. Mary’s formation, 76. areal distribution of, 76. character of materials of, h stratigraphic relations of, 78. strike, dip, and thickness of, sub-divisions of, 78. Sands, discussed, 117. Sassafras Loam, 1383. mechanical analyses of, 138. Sassafras Sandy Loam, 134. mechanical analyses of, 136. Sawmills and their products, 193. y, Thomas, 40. Scharf, J. Thomas, 47. Scott, Joseph, 39. Serub pine, 190. Sedimentary record of Group, 98. of Columbia Group, 99. of Lafayette formation, 98. Sellards, E. H., 53. Shaler, N. S., 45. Shattuck, George B., 7, 17, 25, 50, 52, 53, 67. Silvester, R. W., 5, 153, 176. Sioussat, St. George L., 50. Smith, John, 25, 28, 38. Smith map, 26. Snowfall at Charlotte Hall, 174. Soils, discussed, 125. Soil types, 126. Sotterly, artesian well at, 124. section near, 96. fs 7 Chesapeake Springs, 121. Staggs, T. G., 148, 176. Staves, 197. Stephenson, James, 148, 176. Stratigraphie relations of Calvert forma- tion, 71. of Choptank formation, 74. of Lafayette formation, 83. of St. Mary’s formation, 78. of Sunderland formation, $87. of Talbot formation, 95. of Wicomico formation, 92. Strike, dip, and thickness of Calvert formation, 70. of Choptank formation, of St. Mary's formation, Structure of Coastal plain, 61. Structure and thickness of Lafayette formation, 82. of Sunderland formation, S86. of Talbot formation, 94. of Wicomico formation, 91. Sub-divisions of Calvert formation, 71. of Choptank formation, 74. of St. Mary’s formation, 78. Sunderland formation, 85. areal distribution of, 85. character of materials of, 86. loeal sections in, 90. stratigraphie relations of, ST. structure and thickness of, 86. Sunderland stage, 62. Susquehanna gravel, 129. Swamp land, 8. Swartz, C. K., 7 T Talbot formation, 93. areal distribution of, 93. character of materials of, 95. local sections in, 95. stratigraphic relations of, 95. structure and thickness of, 94. Talbot stage, 64. Telegraph poles, 196. Temperature conditions at Charlotte Hall, 164. Temperature conditions in St. Mary’s county, 151. Tertiary clays, discussed, 114. Thermal anomalies, 155. Topographic history, 61. Transmittal, Letter of, 9. Transportation facilities, 23, 144, 192. Tripoli, 120. True, Frederick W., 53. Tyson, P. T., 44, 45. U Uhler, P. R., 46. U. 8. Bureau of Soils, 17. S. Coast and Geodetic Survey, 30. Department of Agriculture, 18. Forest Service, 18 Geological Survey, 18. U: Weather Bureau, 18. Ulrich, E. ©., 52, 53. = vA Vv Van Renssellaer, J., 38, 40. Vanuxem, L., 34, 40. Variation of the compass, 182. Vaughan, T. W., 52. Veneers, 196, Ww Wagner, William, 42. Wailes Bluff, section at, 96. Warfield, Edwin, 5, 9. Water-horizons in Hocene, 123. in Miocene, 123. Water resources, discussed, 121. White oak, 189. Whitney, Milton, 48. Wicomico formation, 91. areal distribution of, 91. eharacter of materials of, 92. local seetions in, 93. stratigraphic relations of, 92. structure and thickness of, 91. Wicomico stage, 63. Williams, A., Jr., 46. INDEX Williams, G. H., 48. Winds and weather, 176. Windsor Sand, 130. mechanical analyses of, 131. Wood consumption, 192. Woolman, Lewis, 47. ve Yellow poplar, 188. Zz Zones of the Choptank formation, 209 74. 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