Sunday, October 12, 2014

Hickories of Southwest Ohio


(Common expressions of Southwest Ohio Hickory species)

Hickories are a common tree of Midwestern, Southern, and Eastern Forest types. These trees are often characterized for producing edible nuts, strong, flexible, economically import timber, and horticulturally unique aesthetics. In Southwest Ohio, a hickory species finds a niche to sustain itself in within all forest types excluding frequently flooded floodplains dominated by Sycamore, Cottonwood, and Silver Maple typically. Here, we have acidic glacial till deposits often covered in shallow calcareous loess deposits, alkaline glacial outwash, alkaline alluvial terraces, weakly acidic to lightly alkaline residuum soil, and even rare Aeolian sand deposits of which Hickories call home. 

This blog post will provide the specific habitat niche of each hickory species based on topography and soil formation, potential horticultural use, defining I.D. characteristics for local genotypes, and human palatability of nuts.


(Shellbark Hickory-Carya lacinosa occurs as an uncommon calcareous soil obligate in SW Ohio)

Southwest Ohio Habitat


Shellbark Hickory occurs on alkaline alluvial terraces, occasionally flooded alkaline flood plains, and upland weakly acid to alkaline residuum soil formed from Ordovician limestone/shale. It is commonly associated with Blue Ash, Chinquapin Oak, Shumard oak, Bur Oak, Bitternut Hickory, Black Maple, and Sugar Maple.  Thought it is restricted to weakly acidic (6.8 ph) to alkaline (7.0+ph) soil formations here, in in other regions within the midwest, it can occur in more acidic soils.  On thin droughty residuum soils, that typically occur on steep stream dissected valley hillsides, it may occur on lower elevations. Otherwise, it's habitats are of higher moisture availability such as alkaline bottomlands, floodplains, and loess covered soil formations.

Horticultural Use

Shellbark yields shades of gold for fall color consistently on large leaflets of 7 to 9. The glossy fruit, dark green leafs, and shaggy bark offer good summer and winter form. It is safe near buildings, maturing into a large long lived shade tree moderately drought tolerant. This tree will likely thrive where acidic species such as Pin Oak, Red Maple, and Sweet Gum exhibit nutrient deficiencies where soils are weakly acidic-alkaline as it occurs naturally. 

Permaculture Use

Mature trees require harvesting before they drop to the ground due to it's sweet kernel and high wildlife preference. The nut is difficult to crack, but some still consider it worth it for the kernel. 

Key Defining Characteristics


Leaflet of 7 typically, sometimes 9

The shaggy light gray bark of the Shellbark is shares similarity only with Shagbark (Carya ovata) locally. Use the leaflet of 7, and sometimes 9 with the shaggy bark to separate it from Shagbark as Shagbark nearly always has leaflets of 5 locally. In the winter time, if you don't have access to the leaflets, use the very large nuts + Bark to separate Shagbark and Shellbark. Shagbark nuts (not husks) should not be much larger than the circumference of a quarter locally, while Shellbark should have either more spherically or elongated golf ball sized nuts. See first diagram for reference. 



(Shagbark Hickory-Carya ovata is a widely adaptable acidic soil dominating hickory in SW Ohio)

Southwest Ohio Habitat

Shagbark Hickory occurs as a common species in weakly acidic to strongly acidic soils. It is a consistent indicator of sub-7.0 ph soil where naturally occurring and associated with one or more these following species Sweet Gum, Black Gum, Sassafras, Mockernut Hickory, Pignut Hickory, Pin Oak, Black Oak, Scarlet Oak, Red Maple, and/or Yellow Buckeye. It is an indicator of neutral or weakly acidic soil (6.5-7.0 PH) when associated with one or more of the following species Chinquapin Oak, Shumard Oak, or Blue Ash. Because of it's preference for acidic soil and adaptability to low or high moisture availability and poorly drained soils, it finds dominance in Oak-Hickory forest types as well as the Pin Oak-Red Maple-Green Ash forest type that occurs on glacial till plains of variable drainage. One of the best public accessible of a poorly drained acidic glacial till plain forest dominated by Shagbark Hickory occurs at Stonelick State Park in Clermount County. A great example of preferable well drained Shagbark Habitat occurs on the Timberlakes trail of the acidic glacial till covered slopes and uplands of Miami White Water-Great Parks of Hamilton County.


Horticultural Use

The shaggy bark is always a great winter texture, while the fall color is similar to Shellbark, consistently shades of gold. The drought tolerance is high, as well as its tolerance of poorly drained soils, and strong winds making it an ideal tree near buildings throughout the metropolitan. It is a slow grower, and long lived forming an pyramidal canopy in young age, that matures into a more widely spreading canopy in old age. 

Permaculture Use

Mature trees require harvesting before they drop to the ground due to it's sweet kernel and high wildlife preference. The kernel is small but enjoyable.


Key Defining Characteristics


Bark-See above Picture

Leaflet-of 5 nearly always.

What separates Shagbark form all other hickories except for Shellbark Hickory is the nature of it's bark. In the growing season, use the leaflet of 5 paired with the bark to separate it from Shellbark. In the winter, use the nut size comparisons shown in the opening picture + bark. 




(Mockernut Hickory-Carya tomentosa is a hickory at one of it's most northern ranges in SW Ohio)
  

Southwest Ohio Habitat

Mockernut Hickory occurs sporadically in SW Ohio capitalizing on low fertility, well drained, acidic glacial till soils. Miami White Water Badlands Trail and Timberlakes Trail are good areas to see wild growing Mockernut. It is often associated with Black Oak, White Oak, Shagbark Hickory, and Pignut Hickory as well as Sugar Maple and Black Maple.

Horticultural Use

The tightly interlaced bark, coarse branching, and large leaflets of 7-9 offer a nice winter and summer texture to a landscape accented by a often stunning gold-orange fall color. As most hickories, it has great drought tolerance, wind tolerance, and pyramidal form that may branch wider in old age. Slow grower, long lived. 

Permaculture Use

Kernels are small, but sweet while the nut/shell is thick. These are often eaten later by wildlife because of the thick shell/nut, so harvestable in mass by humans due to wildlife focusing on Shellbark, Shagbark, and Sweet Pignut and some Oak species. 

Key Defining Characteristics



Mockernut Hickory requires a couple of different features to definitively separate it from the other hickories. The light colored, non-shaggy bark eliminates all of the hickories except for some expressions of Sweet Pignut (Carya ovalis), and Bitternut (Carya cordiformis). From that point, you can use the size of the Husk+ Nut to eliminate the small fruiting Sweet Pignut and Bitternut Hickory. If fruit is not available, look into the canopy at the terminal buds. If they they are visible from ground level, similar to the size of a Buckeye (Aesculus sp.) bud, then it is Mockernut. This should also coincide with broad branching, thick twigs to support the large fruit that Mockernut produces, unlike the thinner more numerous branching of the smaller fruiting Sweet Pignut and Bitternut. See opening picture for nut size references.     


(Bitternut Hickory-Carya cordiformis is the most common hickory in alkaline soils of SW Ohio)

Southwest Ohio Habitat

Bitternut Hickory is one of the most important hickories of the different upland forest types of Sw Ohio.  It occurs either abundantly or occasionally well drained acidic glacial till, alkaline residuum soil, alkaline alluvial terraces, alkaline glacial outwash, and loess covered soil formations such as Switzerland and Miamian (Hamilton County). It is also intermediate in shade tolerance, reproducing in Beech Maple forests as a minority species.

Horticultural Use

The dark green lightly glossed foliage and texture of the compound leaf of 7 to 9 on thin twigs and pyramidal offers an excellent summer aesthetic in my opinion. The fall color is soft yellow, not a gold or gold-orange like other hickories. Good drought tolerance, high wind tolerance, and pyramidal form when open grown spreading more in old age. 

Permaculture Use

The shell is very thin, able to be cracked safely with teeth like that of an Acorn. The nut meet is coated with tannins that can be leached similar to Acorns.

Key Defining Characteristics



Bitternut Hickory requires a couple of different features to definitively separate it from the other hickories. The light colored, non-shaggy bark eliminates all of the hickories except for some expressions of Sweet Pignut (Carya ovalis), and Mockernut (tomentosa). What then separates this hickory from Mockernut is the significantly smaller fruit as well as the yellowish soft pointed bud. What separates it from Sweet Pignut is again the bud, and the leaflets differ in form of foliage. If you have no access to be buds or foliage, you can compare Bitternut barks and Sweet Pignut bark to see the differences through internet searches. 



(Pignut Hickory-Carya glabra is an occasional species of glaciated SW Ohio)

Southwest Ohio Habitat

Pignut Hickory occurs is restricted to acidic glacial till and is an indicator of acidic soil. It finds a home in Oak-Hickory forest types that occur on glacial till covered slopes low in moisture availability. In the unglaciated Edge of Appalachia preserve in Adams county, it is dominant on dry ridges associated with Shagbark Hickory, Black Oak, Chestnut Oak, and other species. 

Horticultural Use

Due to its superior drought tolerance, perhaps more than any other locally native hickory, high wind tolerance, and typical pyramidal hickory form accented by a gold to golden orange fall color; pignut hickory may be the most useful hickory for the landscape. It also has much smaller fruits than Shagbark, Shellbark, and Mockernut making it less of a "messy" tree. The bark, in maturity, can also be exceptional depending on who's looking at it. 

Permaculture Use

Reports on the kernels have been highly edible with a slightly hard shell, to bad tasting. It may depend on your local genotype, check out this youtube video of a person harvesting and enjoying Carya glabra nuts

Key Defining Characteristics


Leaflet-of 5 nearly always

Fruit-nippled where it was attached to the twig

The leaflet of 5 eliminates all hickories except for Shagbark Hickory. The small nippled fruit then separates it from Shagbark as well as a completely different form of bark. The Bark can be quite similar to Carya ovalis, Sweet Pignut, but differs in fruit as C.ovalis lacks the nipple, and differs in leaflet as C.ovalis is typically 7.



(Sweet Pignut, Carya ovalis-is a widely adaptable, occasional species in SW Ohio)

Southwest Ohio Habitat

Sweet Pignut Hickory differs from Pignut Hickory, in that it occurs occasionally in alkaline soil as well as acidic soil. You can find Sweet pignut as a minority species in nearly all well-drained upland soil formations including acidic glacial till, alkaline residuum, well-drained glacial till plains, and loess covered soil formations. At Lake Hope near Athens Ohio, it may be the most dominant hickory in some areas of the forest finding a preferably habitat in the highly acidic soils there, though local genotypes remain adapted to alkaline soil. 

Horticultural Use

As it finds a niche in alkaline and acidic soil locally, it is indeed an adaptable tree with good open grown form. The fall color isn't as impressive as other hickories giving a dull-gold on good years. The drought tolerance and wind tolerance is likely on par with the other hickories that it competes with.

Permaculture Use

Kernels are sweet, and harvestable from open grown specimens.

Key Defining Characteristics

Leaf-typically of 7





Sweet pignut may prove the most difficult to identify. The leaflet of 7 + small fruit limits your choices to Bitternut and Sweet Pignut. You can either taste the nut, or more scientifically look at the bud. Refer to the above post on Bitternut to see it's bud. Also the bark differs well enough in maturity, but in young age can look similar to Bitternut.