Intraspecific Variation of Growth and Adaptive Traits in North American Oak Species Hb Kriebel

Intraspecific variation of growth and adaptive traits in North American oak species Hb Kriebel

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Hb Kriebel. Intraspecific variation of growth and adaptive traits in North American oak species. Annales des sciences forestières, INRA/EDP Sciences, 1993, 50 (Suppl1), pp.153s-165s. hal-00882886

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Intraspecific variation of growth and adaptive traits in North American oak species

HB Kriebel

School of Natural Resources, Division of Forestry, The Ohio State University, Wooster, OH 44691-4096, USA

Summary — Variation of growth and adaptive traits has been identified in Quercus rubra L, which has recognizable geographic patterns in replicated test plantations in the central and western parts of the species range. Traits varying geographically include growth rate, drought resistance, cold resistance, time of flushing and leaf senescence. Patterns may differ in tests in southern regions. In Quercus falcata Michx, coastal plain sources are superior to others in both central Mississippi and western South Carolina. In 3 partial-range Quercus pagoda Raf tests, local or regional sources out- rank others in growth and adaptability. Both of these species vary widely in cold hardiness. Local trees of Quercus alba L are above the average height of all Indiana trees at age 5 yr in southern In- diana, but local trees of Quercus macrocarpa Michx in Nebraska are not as fast-growing as trees from seed sources 160 km south. Range-wide patterns remain undefined in both of these species. Among western provenances of Quercus nigra L in Louisiana, flushing is latest in trees of the northernmost origins. Only fragmentary information is available on variation of growth and adaptive traits in 7 other oaks, all eastern North American species.

Quercus / oaks / variation / growth / adaptive traits / hardiness

Résumé — Variabilité intraspécifique des caractères d’adaptation et de croissance chez les espèces d’Amérique du Nord. La variabilité des caractères de croissance et d’adaptation a été étu- diée chez Quercus rubra L; des gradients de variation ont clairement pu être établis chez cette es- pèce au vu des résultats obtenus dans des plantations installées dans la partie centrale et occidentale de l’aire naturelle. Les caractères, dont la variabilité suit un gradient géographique, sont : le taux de croissance, la résistance à la sécheresse et au froid, la date de débourrement et la sénescence des feuilles. Ces gradients peuvent être différents dans les plantations installées dans la partie méri- dionale de l’aire. En ce qui concerne Q falcata Michx, les origines des plaines côtières sont supé- rieures aux autres dans la partie centrale du Mississippi, et la partie occidentale de la Caroline du Sud. Dans 3 plantations de Q pagoda Raf ne comprenant qu’un échantillon partiel de provenances, les populations locales étaient nettement supérieures aux autres pour la croissance et les carac- tères d’adaptation. Les origines locales de Q alba L ont une meilleure croissance que les autres dans le sud de l’Indiana (à 5 ans); alors que chez Q macrocarpa Michx dans le Nebraska, les origines locales sont moins vigoureuses que celles originaires de 160 km au sud. Les gradients de variation au niveau de l’ensemble de l’aire naturelle n’ont pas encore été étudiés pour ces 2 espèces. En Louisiane, chez Q nigra L, le débourrement est plus tardif chez les provenances les plus nordi- ques. Des données fragmentaires sur la variabilité des caractères de croissance et d’adaptation exis- tent pour 7 autres espèces, toutes issues de l’est des États-Unis.

Quercus / chênes / variabilité / croissance / adaptation / résistance

INTRODUCTION expected to vary with seed source in experimental plantations. North America has about 58 species of In uniform-environment provenance oaks (genus Quercus) of tree size, of tests of a geographically variable species, which about 20 are considered important extensive provenance sampling covering in forest management (Fowells, 1965). the entire distribution strengthens the provenance in Many of the North American oaks are dis- component of variance relation tributed over a wide range of latitude and to stand and family components, whereas longitude and over several of the plant har- range restriction leads to proportionately diness zones used as guidelines in horti- larger regional and local components (Krie- culture (fig 1, table I). Some are extremely bel, 1965). In several species of Quercus, wide-ranging. Q macrocarpa Michx, one of mid-range or confined-latitude sampling in- the most widely-distributed species, oc- dicated that, within the region studied, curs from 28-53 °N latitude and 66-105 stand variability was more important than °W longitude. Therefore, adaptive traits, geographic variability, and geographic pat- and perhaps growth rate as well, could be terns were not observed (Kriebel, 1965; Houston, 1987; Schnabel and Hamrick, 1990). However, this paper demonstrates that results are very different, at least in Q rubra, when samples are more widely dis- persed. Most of the information currently available on intraspecific variation in the North American oaks is based on population samples covering only parts of the species distribution. Far more information is available on Q rubra than on any other species. In addition, there have been several provenance experiments on Q falcata and the closely-related Q pagoda. Report- ed results from research on Q alba and Q nigra are not range-wide and are limited to juvenile material. Some information is available on growth and adaptatibility of Q macrocarpa from one provenance test at age 11 years. Apart from these 6 species, there is a little information in the liter- ature on variation of growth and adaptive Variation in growth rate traits in North American oaks. Brief dis- cussions on 7 other are included species Northern red oak rubra varies in this review. The information is taken (Quercus L) with geographic origin in rate of height and from: 1) published research; and 2) un- diameter growth. The geographic pattern published data and reports obtained by was evident in trees in 4 the author. With the exception of experi- 23-year-old range-wide tests in middle latitudes of the mental analysis of one commercially im- species range from eastern Nebraska to portant adaptive trait in Q palustris, the in- northern Ohio et al, but not formation on these other oaks is based (Kriebel 1988), at age 14 years in the same tests (Kriebel on fragmentary data from limited popula- et al, There was no statistical evi- tion sampling. 1976). dence of a pattern in results from limited- area sampling (Kriebel, 1965; Farmer et al, La and NORTHERN RED OAK 1981; Houston, 1987; Farge Lewis, 1987). The variation pattern is as follows: About 25 provenance tests of northern red height growth means are almost always oak (Quercus rubra L) of varying size have highest in trees from provenances be- been established in North America, but tween latitudes 43 and 46°N in an east- some no longer exist and others have not west zone extending from the Mississippi been evaluated. Some are comprehen- River to western Maine. Trees from out- sive, multi-family experiments that are side of this zone are, on the range-wide and replicated in several loca- average, slower-growing. In Ohio, Indiana and tions, while others include only a few pop- Michigan experiments, all but one of the ulation samples or are regional in their provenance samples that exceeded the sampling pattern. The first Q rubra prove- mean annual increment of its age class by nance tests, which were established by more than 1 standard deviation was of Scott Pauley in Massachusetts in 1951 Wisconsin, Michigan, Ontario, New York and 1952, were the most geographically or Maine et al, comprehensive tests of this species in origin (Kriebel 1988). There were indications of a similar North America. They included 80 seed pattern in a test of the same material in eastern sources that sampled most of the natural where the distribution. Unfortunately, the plantations Nebraska, fastest-growing trees were from Wisconsin and extreme were not maintained and the only pub- eastern Minnesota (Schlarbaum and Ba- lished report is a study of cold-hardiness. patterns are summar- Nine replicated range-wide tests were gley, 1981). These ized in table II. planted in the North Central states between 1960 and 1962. Results from 7 of From these evaluations up to age 23 these have been published. The other in- years, we can conclude that at latitudes tensive study was of more than 200 fami- 40-42°N in the USA significant gains in lies from Tennessee and adjacent areas; growth of northern red oak can be of 10 outplantings, results from 3 are sum- achieved by planting trees from seed ori- marized. Additional information was availa- gins 250-550 km north of the planting lo- ble from 4 other northern red oak studies, cality. In addition, since growth varies with 2 in the northeastern and 2 in the south- stand and family (Kriebel et al, 1988), intra- eastern parts of the USA. A summary fol- provenance selection is important for plant- lows. ing in this region. We do not know whether the same su- nances in low rainfall regions west of the periority of northern over southern origin Mississippi River, near the range limits, are trees of Q rubra applies to plantations in more drought-resistant than those of other other regions. Fragmentary but inconclu- origins. These differences were observed in sive data suggest that it might not apply in a provenance test in Kansas, at the south- regions farther south. In a replicate of the western limits of Q rubra, where mean sum- above experiments that was planted in mer temperature is highest and mean annu- Kansas, tree diameter was inversely corre- al precipitation is lowest within the species lated with seed source latitude, ie, the range. Trees originating from this region, in- southern provenances had the faster- cluding lowa, Kansas and Missouri, had growing trees. However, data were taken higher survival rates than those from any at age 11 years, and the plantation had other provenance (Deneke, 1975). low survival percentages of all seed source Cold hardiness of northern red oak de- A similar trend samples (Deneke, 1975). pends upon geographic origin. Twigs col- was noted in a progeny test in eastern lected from 16- to 18-year-old trees of 38 Tennessee that included families from origins growing in Massachusetts (Pauley and The Tennessee, Virginia Kentucky. and Johnson, 1955) were subjected to shortest 10 families in mean height at age controlled freezing experiments. Cold har- 20 were from the more northern ori- years diness was strongly related to estimated all the gins (Schlarbaum, 1991). Since mean annual minimum temperature of the seed sources were in a narrow latitudinal origin and to latitude of origin. In all cases, relative to the range species distribution, however, cold hardiness was greater than results are not comparable with those of that required by the climate of the origin, the range-wide tests. suggesting that twig hardiness in established trees is not an important factor in natural selection under contemporary cli- Variation in adaptive traits matic conditions (Flint, 1972). Data of bud-break or leaf flushing of Northern red oak varies geographically in northern red oak depends upon seed drought resistance. Trees from prove- source; in the north central region of the USA, flushing begins in trees of northwest- tamour et al, 1980), with partial replication ern origin, then proceeds ’eastward’ in northern Ohio (author’s records). through trees of northern origin to trees of northeastern origin, and also ’southward’ in rate to trees of central and southern prove- Variation growth nance, ending in trees of mid-latitude origins from southern Michigan to Pennsylva- Seed source had a strong effect on tree nia (Kriebel et al, 1976). This trend is not height in South Carolina at age 10 years. significantly correlated with latitude and it Southern red oaks that surpassed the local is only weakly correlated with longitude source were from the lower coastal plain of (Schlarbaum and Bagley, 1981). In east- North and South Carolina, southern Missis- ern Tennessee, the pattern of flushing is sippi, southeastern and north-central Loui- very different: the general trend begins in siana, southeastern Arkansas and south- trees of southern origins and ends in trees eastern Missouri. Those growing more of northern origins (Gall and Taft, 1973; slowly were from Piedmont and mountain- Schlarbaum, 1991). ous regions of Virginia and North Carolina, eastern Ala- Data of bud-break advances with in- Tennessee, Florida, Texas, bama, southern Missouri and southern crease in seed source elevation; in west- New Jersey. These provenances are near ern North Carolina, the time spread be- the periphery of the species range. No cli- tween the lowest and highest elevation nal trends were found, nor were there any source was 11 days, regardless of planta- meaningful correlations with latitude, longi- tion elevation (McGee, 1974). tude, mean annual temperature or length Unlike the flushing date, the time of leaf of growing season. senescence in Q rubra is very strongly cor- In central provenance ef- related with the latitude of the seed Mississippi, fects at age 5 years accounted for about from north to source, progressing clinally 70% of total variation, and families within south (Deneke, 1975; Kriebel et al, 1976; stands 20%. There was very little differ- Schlarbaum and 1981). Bagley, ence among stands within provenances. Southern red oaks from seed sources in southeastern Texas and eastern Georgia SOUTHERN RED OAK were significantly faster-growing than those from the other 21 provenances. Two principal studies have been conduct- Farther north, in southeastern Pennsyl- ed on geographic variation in southern red vania, the comparison was made between oak (Quercus falcata Michx). One compris- 2 seed sources of southern red oak that are es two 43-origin, range-wide provenance northern for the species and 2 sources in tests in the Piedmont region of western the southern part of the species range. South Carolina (Schoenike et al, 1982). Progenies from seeds collected in the near- The other is a central Mississippi test of by region of Maryland and Virginia outgrew 112 trees from 43 stands in 23 prove- those of Alabama and Arkansas origins. nances, including most of the natural distribution with the exception of Florida and areas north of 36°N (Mukewar and Land, Variation in adaptive traits 1987). In addition, a few families of 4 provenances were tested at the Michaux Quer- Survival of southern red oak in South Car- cetum in southeastern Pennsylvania (San- olina and Mississippi is not source-related. In southeastern Pennsylvania, it is; trees the tallest of the Tennessee families had a from Mississippi suffer heavy mortality mean height of ≈ 11 m, 2-6 m above the from winter temperatures. Trees of Arkan- means of southern and western trees (Uni- sas sources are less affected, but of the 4 versity of Tennessee, unpublished data). and provenances tested, only Virginia In a more recently initiated study near Maryland trees had high survival rates the Mississippi River in extreme northwest- et In where (Santamour al, 1980). Ohio, ern Kentucky (including provenances from winters are more severe, trees of the Vir- Louisiana, Mississippi, Alabama, Tennes- seedlot that were in ginia hardy Pennsylva- see, Kentucky and Virginia), the trees from nia all died within the first few after years Tennessee and Mississippi were outgrow- Other sources were not tested planting. ing those from other sources at age 5 (author’s records). years. Some were 6 m in height (Rous- seau RT, unpublished data). Farther in CHERRYBARK OAK north, Indiana, cherrybark oaks from the northern extremity of the species range in southern Indiana were Harlow et al (1991) now follow Jensen significantly taller than all others at age 7 (1989) in classifying cherrybark oak as years. The test included 9 seed sources in Quercus pagoda Raf rather than as a form 6 states (M Coggeshall, unpublished anal- of southern red oak (Quercus falcata var ysis and these proceedings). pagodaefolia Ell). The 2 oaks were considered by Ware (1967) and Jensen to be sister species that are incompletely repro- Variation in adaptive traits ductively isolated. In support of species separation, Jensen stated that, "differences between them can be detected consistent- Cherrybark oak is highly variable in cold ly in geographically widespread locales, in- hardiness. In western Tennessee, families dicating that recognition of these taxa as of local origin averaged 92% survival at species is in keeping with the generally ac- age 10 years, while those from Mississippi cepted species concept in oaks." Q falcata and Arkansas averaged 66% (Overton, characteristically occupies a xeric habitat, 1981). In southern Indiana, Coggeshall’s whereas Q pagoda occurs in mesic habi- records show that only trees from extreme tats. southwestern Indiana, the northernmost point in the species range, remained completely healthy after a 10-day period with a Variation in growth rate low temperature of -31°C. There was a high negative correlation between degree of winter injury and seed source latitude. Cherrybark oak has been described as the most southern oak (Ran- rapidly growing WHITE OAK dall, 1972). As in Q falcata, the growth rate of Q pagoda is very dependent upon seed source. In a western Tennessee test that White oak (Quercus alba L) grows through- included 36 phenotypic selections at age out the eastern United States, with the ex- 10 years, trees from Mississippi and Ar- ceptions of northern Maine and the Florida kansas seed sources grew poorly com- peninsula. It also occurs in parts of south- pared with those from the Tennessee ern Ontario and Quebec. Although it is one sources (Overton, 1981). By age 14 years, of the most common and commercially important oaks in the eastern United States, There was no evidence from any of there is no range-wide provenance test of these limited-sample Q alba experiments the species. The most geographically dis- that survival rate was related to the geo- persed set of population samples is in the graphic origin of the seed. Michaux Quercetum test in southwestern Pennsylvania, which includes small num- bers of trees of 18 families from 9 prove- BUR OAK nances (Santamour et al, 1980). Eight of these provenances are replicated in Bur oak (Quercus macrocarpa Michx) has Wooster, Ohio. There are 2 tests estab- a wide north-south natural distribution lished by Coggeshall in southern Indiana very (table I), extending from Manitoba nearly to containing 63 and 70 families from the Gulf of Mexico. It also has a wide longi- Indiana. Results from an un- throughout tudinal from New Bruns- evaluation of in the range, extending published 5-year-old wick far into the Bur oak is ex- Indiana tests sent to the author prairies. by Cogge- tremely drought-resistant (Fowells, 1965). shall are included in this review. Provenance variation has been studied in eastern Nebraska and on a smaller scale in eastern Pennsylvania and Ohio. Variation in growth rate

No geographic pattern of variation in Variation in growth rate growth rate was evident among 24-year- old white oaks of 9 provenances in Penn- In eastern Nebraska, a test of 50 seed sylvania. The sampling dispersion was sources the but from Massachusetts and in the sampled species range, Virginia was concen- east to Wisconsin and Arkansas in the population sampling mainly trated in Kansas and Nebraska. Height at west (Santamour et al, 1980). Results age 11 years was maximum in trees origi- were the same in the Ohio replicate at age nating 160 km south of the plantation at 11 years (author’s data). This absence of 40 °N. There was no observed continuous a pattern is not surprising, considering the geographic pattern of growth rate (Dicke small number of provenances and the vari- and Bagley, 1980). In eastern Pennsylva- ation among seedlots. In southern Indiana, nia, only 2 seedlots each from Kansas, where 5 latitudinal transects were made, South Dakota and Minnesota were tested. 2 stands per transect, dif- including family tended to increase with de- ferences were about 2.5 times stand differ- Height growth creasing latitude of seed origin; Kansas ences. Stand, transect and stand-within- trees about 1.5 times the transect differences were not at averaged height significant of Minnesota trees et either test location. Growth of trees from (Santamour al, local stands exceeded the test mean at 1980). both test sites. These early Indiana results suggested that, in that region, some gain Variation in adaptive traits in growth of white oak may be obtained by using seed sources (or stands) from a latitude of up to 2 °N of the planting site, but Date of leaf fall was not related to the lati- that extreme northern Indiana seed should tude of the seed origin in Nebraska. In be avoided for planting in southern India- southeastern Pennsylvania, survival rate of na. bur oak by age 25 years was 4 times higher among Kansas trees than among Min- trees of more northern origin. A late frost nesota trees. Since the test site has a mild- damaged foliage of local and southern er winter climate and higher precipitation provenance material, but there was no in- than either the Kansas or Minnesota col- jury to the Arkansas trees (Adams, 1989). lections, the differential survival does not In southeastern Pennsylvania, near the appear to reflect differences in either cold northern range limits, survival of trees of hardiness or drought resistance. Bur oaks Virginia provenance was highest, averag- from these 2 sources had a high survival ing 76%. Survival of Maryland and Missis- rate in northern Ohio. sippi trees was lower (Santamour et al, 1980). Only 3 trees from one source (Vir- ginia) were tested in northern Ohio, a cold- WATER OAK er climate than southeastern Pennsylva- nia. Records show that all 3 were growing at age 11 years. Water oak (Quercus nigra L) is a southern, mild-climate species. At its northernmost limits, mean minimum winter temperature OTHER NORTH AMERICAN OAKS is -18 to -12°C (US Dep Agric, 1960). Most information on geographic variation is available from one 5-year-old provenance With the exception of one study of Quer- test in central western Louisiana and from cus palustris Muenchh, information on vari- southeastern Pennsylvania. ation of growth and adaptive traits in other oaks is based on the testing of open- pollinated progenies at the Michaux Quer- Variation in growth rate cetum, Longwood Gardens, PA. Seed samples from various North American oaks were collected from a small number In Louisiana, 68 water oak families were of trees in each of 2-9 geographically dis- taken from 12 sampling points in the west- persed localities. Trees from each seedlot ern part of the species distribution, consist- were divided into 2 row-plot replicates; the ing of 3 north-south transects, one along total number of trees planted per seedlot the Mississippi River and the others 160 varied from 11 to 42. Analysis of juvenile km east and west of it. At age 5 years, material indicated that there was genetic there was no distinct geographic pattern. variation in growth and phenology, but no Trees from the middle Mississippi River geographic patterns could be identified and middle eastern Mississippi sources (Gabriel, 1958; Santamour and Schreiner, were in both diameter consistently high 1961; Schreiner and Santamour, 1961). An and height growth, but trees of southwest- assessment of growth and survival of all ern Louisiana which 4.2 m origin, averaged oak collections in the Quercetum was at age 5 years, were superior overall in made at age 25 years (Santamour et al, rate of height growth independent of diam- 1980). Three-tree plots of many of the eter (Adams, 1989). Quercetum collections were planted by Kriebel at Wooster, Ohio and measured at age 11 years. The data were not published Variation in adaptative traits and a large part of the test was subse- quently lost due to road construction. Giv- Q nigra trees of northern Arkansas origin en the limitations of these experiments, the flushed 7-10 days later in Louisiana than results nevertheless report the perfor- mance of source-documented trees and the average than trees from the Tennes- provide some useful information on growth see provenance. and climatic adaptability in relation to provenance. Black oak

Pin oak There are 11 seed lots of 6 provenances of black oak (Quercus velutina Lam), in the Experiments with pin oak (Quercus palus- 25-year data from Pennsylvania. Seed ori- tris Muenchh) on 19 natural and 2 cultivat- gins include Alabama, Tennessee, North ed populations well-distributed throughout Carolina, Virginia, Illinois and Michigan. the natural distribution were designed and The Ohio collections originally included 8 carried out to evaluate the severity of iron Q velutina seedlots from the same prove- chlorosis in solution culture and soil envi- nances and Connecticut. In southeastern ronments. There were significant differenc- Pennsylvania, seedlot differences in 25- es in resistance among the progenies of year height growth within provenances different pin oak parents, but the rankings were small. Although black oaks of Ten- varied considerably among experimental nessee and Illinois origins were slightly environments. There was some indication faster-growing than others, averaging of a geographic pattern; population sam- 16.3 m, North Carolina trees had the high- ples from northcentral and northwestern est survival rate. In northern Ohio, the parts of the species range (Indiana, Illi- mean height of one Michigan family was nois, Missouri) were consistently among 30% greater than the mean of 2 Tennes- the most resistant populations. One popu- see families. Black oaks of Alabama origin lation from northern Illinois was a particu- were not winter-hardy in Ohio and there larly promising candidate for testing and was dieback of Virginia and North Carolina selection (Berrang and Steiner, 1980). trees.

Shumard oak Scarlet oak

In Pennsylvania, the growth rate of Shu- The Michaux Quercetum plantings include mard oak (Quercus shumardii Buckl) was 4 provenances of scarlet oak (Quercus higher in trees of Mississippi provenance coccinea Muenchh) in Pennsylvania and 3 than in trees from Illinois, Tennessee and in Ohio. In Pennsylvania, trees from Ten- Florida sources. Juvenile trees of all nessee and Illinois seedlots had a mean sources except Illinois had an extended height at age 25 years of 15.5 m, a slight growing season and were killed back by superiority over the growth of Virginia and early fall frosts. However, at age 25 years, Alabama trees. Survival differences were the 70% survival rate of Shumard oaks of not source-related. Of the 3 provenances Mississippi origin was nearly as high as represented in Ohio, trees from the one that of Illinois trees and growth rate was Virginia provenance were 36% faster- higher, up to 17.1 m. In the colder climate growing at age 11 years than the mean of of northern Ohio, the Mississippi and Flori- 2 Tennesee provenances. Scarlet oaks da collections were not winter-hardy. from Alabama seedlots did not survive in Trees of Illinois origin were 17% taller on Ohio. Willow oak CONCLUSIONS

Six seedlots of 4 provenances of willow With the exception of results from tests of oak (Quercus phellos L) were tested in Quercus rubra, information on variation in Pennsylvania. The provenances were Mis- growth and adaptive traits of the North sissippi, Arkansas, Virginia and Maryland. American oaks is still very limited. Even Willow oaks of Virginia origin were tallest Q rubra is inadequately sampled, consid- with a mean height of nearly 16 m at age ering its abundance and wide distribution. 25 years, but only one-third of the trees The distribution of Q falcata has been survived the winters. The survival rate of more completely sampled than has that of trees in the Arkansas collections was the wider-ranging Q rubra, although the about twice that of the others. Only Arkan- future of the South Carolina tests of sas trees were winter-hardy in Ohio, but southern red oak is uncertain. However, growth was slow, averaging 1.5 m at age some useful information is now available 11 years. about intraspecific variation in growth rate and winter hardiness in this species. Stud- ies of variation in Q pagoda are yielding Shingle oak valuable information, but they do not cov- er the entire species range. Considering the economic of Q alba, we Shingle oak (Quercus imbricaria Michx) importance should be much farther ahead than we was represented in both Pennsylvania and are in our research on this species. Our Ohio by 3 sources (Illinois, Indiana and white oak tests are very limited, both geo- Ohio). There were no clear source-related graphically and in sampling intensity. Be- differences in growth rate or hardiness in cause of its drought-resistance in the prai- either location. At age 25 years in Pennsyl- rie of North America, Q vania, trees of Indiana origin averaged regions macrocarpa merits further research on 15.6 m in and were taller than those height and hardiness. The initiated from Illinois and Ohio. vigor recently effort under way with Q nigra, focusing on the western part of the species range, will some information on this Blackjack oak provide previ- ously untested fast-growing species. Tests of scattered seed sources of 6 other One progeny of each of 4 provenances of oaks provide fragments of information blackjack oak (Quercus marilandica thay may reduce the risk of plantation fail- Muenchh) was tested in southeastern ure and increase productivity in certain re- Pennsylvania. The provenances were in gions, although they are at best only indic- Texas, Kansas, Arkansas and New Jersey. ative and in no case descriptive of Height growth in 25 years varied from a variation of the species as a whole. Indi- mean of 9.4 m for trees of Texas origin to cations of variation in resistance to iron 7.2 m for trees from the New Jersey seed chlorosis in Q palustris may be useful in source. The survival rate of blackjack oak urban forestry. 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