Lithocarpus

( lith - oh - KARP - uss )

At-A-Glance Information

This genus of evergreen trees, commonly known as Stone Oak, includes species which need full sun to light shade and moderate water to perform well in the garden. These attractive ornamental trees are typically used in park landscapes or large gardens as shade trees; they are not suitable for small gardens or container plantings. Use these trees as specimen or shade trees or as background plantings. Stone Oaks are also wonderful wildlife supporting additions to the garden, providing habitat and food for local animals.

Lithocarpus species and varietals

The genus Lithocarpus is a member of the plant family Fagaceae and includes around 340 species. These trees are closely related to Oak (Quercus) and Chestnut (Castanea). The best growing zones for Stone Oak vary depending on the species grown; for more information see the species descriptions below. ​To find your zone, click here: Zone Map.

Lithocarpus andersonii (Anderson's Tanbark Oak)
Endemic to Borneo where it grows in lowland swamps and forested areas, this species of Stone Oak reaches up to 100 feet tall with a trunk diameter of 24 inches. Bark is smooth and brownish. Leaves are dark green. This species is named for Borneo Forest Officer James A. R. Anderson.

Lithocarpus bancanus (Stone Oak, Ko Wong Lat, ก่อวงเอียด)
These trees are native to Thailand, Borneo, Peninsular Malaysia, and Sumatra, where it grows in hilly areas and peat swamp forests. The specific epithet for the species means 'of Bangka', which is an island east of Sumatra. Individual trees reach up to 80 feet tall when mature and have yellow-grey bark that is smooth to scaly.

Lithocarpus conocarpus (Stone Oak, Pasania, Mempening, Singapore Oak)
These trees reach 150 feet tall when mature, and have scaly, grey-brown bark and green foliage. They are native to Sumatra, Peninsular Malaysia, Singapore, Java, and Borneo, where they grows in lowland montane forests. The specific epithet conocarpus means 'cone fruit', referring to the acorn-shaped fruits produced by these trees. Best in USDA hardiness zones 11 and 12.

Lithocarpus coopertus (Barusang, Bohol Oyagon, Iloko, Stone Oak, Spike Oak)
Native to Malaysia, Borneo, and the Philippines, these trees reach up to 110 feet tall and have 28-inch trunks. Bark is smooth and greyish-brown. Foliage is green. The specific epithet coopertus means 'covered over', referring to the acorn fruits that have coverings. This species of Stone Oak is suited for USDA hardiness zones 10-12.

Lithocarpus densiflorus (Notholithocarpus densiflorus) (Tanbark Oak, Tanoak, Stone Oak, California Tanoak)
​These trees can reach 80 feet tall and 50 feet wide, but in most gardens only reach to half their full height. Leaves are leathery and toothed and tiny, white male flowers bloom in summertime followed by acorns. These trees are native to woodlands in the coastal ranges from Oregon down through southern California. Tanbark Oaks do well in USDA hardiness zones 7a-10b and Sunset growing zones 4-7 and 14-24.

Lithocarpus dodonaeifolius (Stone Oak, Lie Ye Ke, 柳叶柯, Willow-Leaf Lithocarpus)
These trees are quite similar to those in the species Lithocarpus formosanus, and reach up to 30 feet tall. They are endemic to Taiwan, and produce green foliage. Willow-Leaf Lithocarpus is considered endangered in its native range.

Lithocarpus edulis (Japanese Stone Oak, Tanbark Oak, Japanese Tanoak, Stone Oak)
This species is native to Japan, and forms an evergreen tree that reaches up to 50 feet tall at maturity. These trees are cultivated as ornamental landscape plants. Nuts produced by these trees are technically edible, though they are very bitter. Soaking them in water will remove tannins. This species grows well in USDA hardiness zones 7-10 or Sunset growing ones 7, 9, and 14-24.

Lithocarpus elegans (Elegant Himalayan Oak, Sunda Oak, Spike Oak)
Native to the Indian subcontinent, Indo-China, and Malesia, these trees have greyish-brown bark and produce edible brown acorn fruits. Trees reach about 100 feet tall when mature. The specific epithet elegans refers to the acorns and cupules produced by these trees. Elegant Himalayan Oak is suited for USDA hardiness zones 10-12.

Lithocarpus formosanus (Taiwan Tanoak, Willow-Leaf Tanoak, Formosan Tanoak, Taiwan Shili, 台灣石櫟 , Taiwan Ke, 台灣柯 )
Endemic to Taiwan, this medium sized tree forms a crooked trunk with many branches. Leaves are green. These trees are critically endangered in their native range due to habitat destruction. Mature trees can reach up to 33 to 50 feet tall. Taiwan Tanoak is suited for USDA hardiness zones 10 and 11.

Lithocarpus havilandii (Haviland's Stone Oak, Stone Oak)
This species is named for British surgeon and naturalist George Darby Haviland, and reaches up to 80 feet tall with a trunk diameter of up to 16 inches. Bark is smooth to flaky and greyish-brown. These trees grow naturally in Borneo and Sulawesi and are suited for USDA hardiness zones 10 and 11.

Lithocarpus leptogyne (Mempening, Spike Oak, Sunda Oak)
These trees tower at 130 feet tall when mature, and form buttress roots up to 5 feet high. Bark is smooth or lenticellate and grey-brown. Acorns are brown to purple in color when ripe. This species grows well in USDA hardiness zones 10 through 12, and is typically cultivated as a timber tree.

Caring for Lithocarpus

The first step in caring for Lithocarpus trees is the selection of the perfect planting site. These trees thrive in full sun to partial shade. They will tolerate afternoon shade, especially in hot climates, but perform best when they receive at least 6 hours of direct sunlight every day. The planting spot should also be able to accommodate the full size of these trees, including the root system. These trees can grow to be quite large, and do not like to be crowded. Ensure that soil is well-draining; if local soils are compacted or overly clayey, make sure to amend the planting site with plenty of organic material and/or sand before installing. Lithocarpus trees prefer a soil pH of between 5.5 and 7.0 (neutral to slightly acidic). They thrive in loamy, rich soils but can also tolerate others, as long as they do not stay waterlogged for long periods of time. Apply a thick layer of mulch to increase soil moisture retention, suppress weed growth, and regulate soil temperatures. New trees should be watered regularly. Once mature, apply irrigation deeply in periods of drought and during summertime; in areas with normal precipitation they can get by with just rainwater alone for the rest of the year.

These trees are tropical and therefore sensitive to cooler temperatures. They prefer a climate that stays between 60 and 85 degrees Fahrenheit for most of the year, and will need protection from cold. New plantings should be protected with frost cloths over the winter months. If cool temperatures kill younger plants to the ground, they have the ability to regrow from roots if heavily mulched. Prunings are completed primarily to remove dead, damaged, or diseased wood and to shape trees. They naturally have a very handsome canopy shape. Regular prunings (once a year) are sufficient to maintain a tidy appearance and prevent overcrowding of branches. Lithocarpus are long-lived trees, surviving for between 300 and 350 years or more in the wild. When they are grown in urban environments or smaller landscapes, their life span is shortened by 50% or more.

Propagation

Lithocarpus can be propagated either by using cuttings or from seed. To ensure that your propagated plant will have the exact same qualities and characteristics as the parent plant, use the cutting method. If you would like to experiment and see what plant you can grow from seed, just keep in mind that it will not necessarily be the same as the parent plant. To propagate your tree, follow the instructions below:

Propagating Lithocarpus by Cutting
  1. Gather your materials. You'll need a clean, sanitized, sharp pair of garden shears, rooting hormone, a pencil, and a 3-inch pot filled with well-draining compost or other organic material. A good substrate for propagation of cuttings is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
  2. In spring or early summertime, choose the plant that you'd like to propagate. Ensure that this plant has had a good watering the night before, as this will improve the chances your cutting will take root. Cut one or more 6 inch semi-hardwood portion(s) of the end of a non-blooming branch and strip the leaves off of the lower half. Make a hole in your planting medium by pushing your pencil into the soil. Dip the end of the stem in rooting hormone, and plant it in your pot. Fill in soil around the cutting to support it, but do not pack it down too much.
  3. Moisten with water, and ensure that the pot has good drainage. Your pot should be kept in warm, sunny conditions indoors (and not in direct sunlight). Water whenever your soil is dry under the top layer. After about four to six weeks have passed, your cutting should be rooted. When you notice new growth, you'll know you have roots. 
  4. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring, when you can transplant it to its new home. Ensure that the last frost of the year has occurred before doing this, as it can seriously damage your new tree.

Propagating Lithocarpus by Seed
  1. Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant. To propagate by seed, you will need a paper bag, a pot or tray filled with well-draining compost or other organic material, a spray bottle and a fork. The best potting medium for seed germination is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
  2. Harvest your acorns. Mature acorns will begin to drop from trees in autumn. Harvest those still on trees, as they are less likely to have been attacked by pests or disease than those on the ground. 
  3. Lithocarpus acorns need a period of cold-stratification to germinate. Place seeds in a sealable container or plastic bag filled with moistened sphagnum moss or sand. Then, put the container in the refrigerator and leave it there for between 60 and 90 days' time. Ensure that the stratification medium stays consistently moist but not waterlogged during this time.
  4. Water your prepared seed tray or pot filled with soil, and ensure that good drainage is occurring. Place your seeds in your prepared pot or seed tray about an inch or two under the soil surface. Cover them with soil and water with your spray bottle. Place your seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes 6-8 weeks from sowing. Once you begin to see seedlings sprout and they are able to be handled, transplant them to their own individual 3-inch pots, filled with the same potting medium as described in Step 1. Loosen the seedlings from the potting medium by digging down with the tines of your fork about an inch and a half, gently working the seedling up until it is out. Then, replant the seedling in its individual pot.
  5. Keep the seedling's potting medium moist, but not wet, by spraying the soil with your spray bottle. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring (after the danger of frost has passed), when you can transplant it to its new home.
Lithocarpus trees and shrubs produce acorns that are typically mature in autumn.
Lithocarpus acorns are light brown to reddish-brown.

Problems and Pests

Lithocarpus trees are susceptible to the following pests and diseases:
  • Phytophthora ramorum (Sudden Oak Death)
  • Aphids
  • Scale Insects
  • Caterpillars
For more information on these pests and diseases, including how to solve them when they pop up, consult the following pages:
​

Gallery

Bark on mature trees is uniquely fissured, and is typically tan, hence the common name Tanoak.
These tropical trees are sensitive to cold, and appreciate a dressing of mulch around theri base.
Flowers are typically white to yellow and form towards branch tips.

Videos

How to collect seed from Lithocarpus trees.
Check out these tropical Oaks.

Resources

Wikipedia: List of Lithocarpus Species
Wikipedia: Lithocarpus
The New Sunset Western Garden Book: The Ultimate Gardening Guide (2012) - Page 418, Lithocarpus densiflorus