Monday, March 4, 2013

Permaculture Plants: Pecans and Hickory


Pecans... a favorite nut!

Common Name: Pecan and Hickory
Scientific Name: Carya species
Family: Juglandaceae (the Walnut family)

Hickory Nuts

Common Species:
  • Pecan (Carya illinoinensis) – large to very large tree
  • Shellbark Hickory (Carya laciniosa) – large tree
  • Shagbark Hickory (Carya ovata) – large tree
  • Hican (Carya x hybrids) – large to very large tree

Shagbark Hickory (Carya ovata)... Stunning!

Less Common Species:
  • Water Hickory (Carya aquatica) - large tree, used mainly for wood and fuel
  • Chinese Hickory (Carya cathayensis) - large tree, used for nuts, oil (nut), and wood
  • Bitternut Hickory (Carya cordiformis) - large tree, used mainly for wood and fuel
  • Pignut Hickory (Carya glabra) - very large tree, variable flavored nut, used mainly for wood and fuel
  • Mockernut Hickory (Carya tomentosa) - very large tree, good flavored nut but very tough shell, used mainly for wood and fuel 

A majestic Pecan tree

Description:
The Hickories and Pecans are large, slow-growing trees that can take many years to begin bearing. These majestic trees which give us some of the best tasting nuts, fantastic wood wood for smoking meat, and wood that can be used in a variety of ways, should be considered an investment for the future. I hope to enjoy, literally, the fruits of my labor, but I know my children, grandchildren, and maybe even my great-grandchildren will enjoy it as well.

Pecan (Carya illinoinensis) by Charles Sprague Sargent

History:
Native to Asia and North America, Hickories and Pecans have been used for food, wood, and fuel since people have been around to use them. These trees have been developed for larger and sweeter nuts, and the Pecans have had the most development so far.

Trivia:
  • The name “Hickory” comes from the Algonquian Indian (Native American people group) word pawcohiccora, meaning the nut from the Hickory tree.
  • Pecan and Hickory Nuts are not technically nuts… they are considered “drupes” or even "tryma". A drupe is a fruit with a single seed inside. So the “nut” of these plants have a soft fruit that dries and splits to reveal the seed… what we call the nut. A true nut is a fruit which forms a hard shell to cover the seed, and this hard shell (the fruit) does not split open on its own. Confused yet? It may be easiest to call it a nut!
  • “Papershell Pecans” are pecans that have such thin shells that the shell can be cracked by just squeezing together two nuts in your hand… some are so thin, that the shells can be cracked by just squuezing one nut between two fingers. However, these nuts are much more prone to cracking on the tree when the nut swells during heavy rains.
  • Pecans have nuts
  • Shagbark Hickory have nuts about 1.5 inches (4 cm) long
  • Shellbark Hickory have nuts about 2.5 inches (6 cm) long
  • The Hican is a cross between a Pecan (C. illinoinensis) and another Hickory species (Carya species)… so in reality, there are a wide variety of trees appropriately named Hican. Most hybrids have poor nuts, but the named Hicans typically produce very large and tasty nuts; although, they usually produce less nuts than either of its parents.
Pecan Pies would be reason enough to plant these trees.

USING THIS PLANT
Primary Uses:
  • Nut – Raw. Excellent taste in both Pecans and selected Hickories.
  • Nut – Cooked. Used in desserts, breads, baking, etc.
  • Nut – “Milk” can be made from Pecan nuts
  • Nut – Oil. An edible oil can be pressed from Pecans

Secondary Uses:
  • General insect pollen plant – attracts beneficial insects which feed on the pollen of these trees
  • Wildlife food
  • Wildlife shelter
  • Windbreak plant
  • Sap is edible (Hickories) – can be tapped like Maples and reduced (with heat) to make syrup. I have yet to try this syrup, but the reports on flavor I have found range from very good to fair and slightly bitter. Interesting.
  • Coppice Plant
  • Wood used for poles, posts, fence posts, stakes, tool handles (axes!).
  • Wood used for fuel (firewood), charcoal.
  • Wood is a great wood for smoking meats.
  • Dynamic Accumulator – Potassium and Calcium for all species; Phosphorus in Shagbark Hickory (C. ovata)
  • Biomass Plant – large tree with lots of leaf-fall every Autumn that can be left to decompose and build the forest soil, or it can be moved and used in other places or composted.

Yield: 
Highly variable on species and size of the tree. Hickories produce less than Pecans; Improved varieties often produce more than unimproved and wild species, although the hybrid Hican will produce less (but larger) nuts than the Pecan. 50 lbs (23 kg) is not uncommon for a 10-20 year old tree. Pecans can produce up to 100 lbs (46 kg) when they are 20-25 years old. A mature Pecan that is 75 years old or older can produce close to 500 lbs (225 kg) of nuts. There are some Pecans that have yielded over 1,000 lbs (450 kg) of nuts in a season!

Harvesting: Autumn. Although if you have Pecans in more warm locations, you may harvest all the way through January. Pecans and Hickory are typically harvested after they have fallen from the tree; however, some people (and commercial operations) use nets to catch the nuts during harvest season.
Storage: Can be used right away, but if the nuts are dried, they can store for a few years.

The long, thin, green flower clusters ("catkins") of a Pecan tree

DESIGNING WITH THIS PLANT
USDA Hardiness Zone:
  • Pecan (Carya illinoinensis) – Zone 6-9
  • Shellbark Hickory (Carya laciniosa) – Zone 6
  • Shagbark Hickory (Carya ovata) – Zone 4-7
  • Hican (Carya x hybrids) – Zone 5

AHS Heat Zone:
  • Pecan (Carya illinoinensis) – Zone 9-1
  • Shellbark Hickory (Carya laciniosa) – Zone 8-1
  • Shagbark Hickory (Carya ovata) – Zone 8-1

Chill Requirement: 650-1,550 hours/units depending on the species/variety.


Plant Type: Large to very-large Trees
Leaf Type: Deciduous
Forest Garden Use: Canopy Layer
Cultivars/Varieties: A few very worthwhile species. There are quite a few cultivars and hybrids available.

Pollination: Self-Sterile (although a few varieties are self-fertile). Requires cross-pollination by other cultivars for the nuts to be produced. Pollinated by the wind. Trees can be pollinated by the wind carrying pollen from other trees up to 10 miles away!
Flowering: Late Spring to Early Summer.

Life Span:
Years to Begin Bearing: 3-10 years for Pecans (sooner in the south); 40 years for wild Hickories (only 3-7 years if the tree was grafted)
Years Between Major Cropping: 1-2 years
Years of Useful Life: minimim of 100 years, but most will be productive for at least 200 years. It is not uncommon for trees over 400 years old to still produce large yields.

Shagbark Hickory Nuts

How the Shagbark Hickory got its name...

PHYSICAL CHARACTERISTICS OF THIS PLANT
Size:
  • Pecan (Carya illinoinensis) – 75-120 feet (22-36 meters) tall and wide
  • Shellbark Hickory (Carya laciniosa) – 70-85 feet (21-25 meters) tall and 30-50 feet (9-15 meters) wide
  • Shagbark Hickory (Carya ovata) – 70-85 feet (21-25 meters) tall and 30-50 feet (9-15 meters) wide
  • Hican (Carya x hybrids) – 75 feet (22 meters) tall and 50 feet (15 meters) wide

Roots: Single, large taproot
Growth Rate: Slow. Some improved varieties grow at a bit faster rate than the wild species.

Shellbark Hickory (Carya laciniosa)
Check out this site for a great photo resource on Carya species: 

GROWING CONDITIONS FOR THIS PLANT
Light: Full sun
Shade: Some species tolerate light shade; the Shagbark Hickory (C. ovata) can tolerate a bit more shade than the other species. The Pecan (C. illinoinensis) doesn’t like any shade.
Moisture: Medium soil moisture preferred. The Shellbark Hickory (C. laciniosa) can tolerate more wet soils. The Shagbark Hickory (C. ovata) can tolerate some fairly dry periods and doesn’t like wet soils or flooding.
pH: most species prefer fairly neutral to alkaline soil (6.5-8.0)

Special Considerations for Growing:
  • Almost all of these trees are slow growing during their first few years.
  • Most species/varieties require a hot summer to thrive.
  • All species tolerate juglone (natural growth inhibitor produced by Black Walnut and its close relatives… Pecans and Hickories are more distant relatives of the Walnut). Consider using this tree as a buffer between your walnuts and other plantings.

Propagation:
From seed – needs at least 3 months cold stratification to germinate. If starting from seed, make sure to use deep pots to give room for the taproot. Get the seedlings into their permanent spots as soon as possible to avoid damaging or stunting that taproot. Ideally, if you can protect the seeds from mice, the seeds would be planted where you want the trees to grow. Named varieties are available from grafting.

Maintenance:
Very little. Once established, almost none.

Concerns:
Truly none. However, I have my own personal concerns about the grafted varieties. The majority of Pecans are grafted onto only a few rootstocks. Granted, these rootstocks are very hardy and resistant to many diseases, but I don’t like the idea of putting all my eggs in one basket. What if a disease came along that knocked out those few rootstocks? It is highly unlikely, but what if? My goal with my (future) forest garden is not to be a commercial producer of one thing (in this case, Pecans or Hickory Nuts). My goal is to create a bountiful and resiliant ecosystem. So what will that mean in practice? Well, I will certainly have a number of named varieties of Pecans on the standard rootstocks, but I will also likely grow some of my own trees from seed. This may delay the onset of nut production for many years, but I think it is a great legacy to leave. To know I planted something that my children and grandchildren will enjoy, even when I did not, sounds pretty great to me.

3 comments:

  1. Love Pecan nuts but never had hickory nuts. Neither of those species grows anywhere i am familiar with. I do get to see some great wing nuts and walnuts

    ReplyDelete
  2. Strange thing is that they tell it don't grows in Quebec but I found a tree near river. Where the water level rise at spring and go back at summer. Real damp soil with lot of frogs around and plants you see only in really humid environnement. Water lily grow there too.

    ReplyDelete
  3. spot on! a legacy of pecans and hickory nuts for the future sounds pretty darn good

    ReplyDelete