Juglans nigra
Common name: 
Black Walnut
JU-glanz NIG-ra
Native to (or naturalized in) Oregon: 
  • Broadleaf deciduous tree, 50-75(125) ft, [15-23(38) m], long trunk, oval to round crown.  Bark dark brown to grayish black, divided by deep, narrow furrows.  Leaves alternate, large pinnate, 30-60 cm long, from 15-23 leaflets (occasionally as few as 11), terminal leaflet frequently missing, each leaflet 5-13 cm long, 2-5 cm wide, ovate-oblong to ovate-lanceolate, acuminate tip, rounded base, irregularly serrate, fragrant when crushed.  Fruit (nut) spherical, glabrous light green (4-5 cm diam.), grainy surface.  Pith of stem uniformly chambered.
  • Sun.  Prefers deep, rich, moist soils, tolerates drier soils but grows much more slowly.  Extensive taproot and is difficult to transplant.  Wood valuable.  Difficult to garden under since J. nigra inhibits the growth of other plants.  Some plants, however, tolerate this situation, including selected annuals, bulbs, and herbaceous perennials.  Woody plants that can be grown under walnuts include, species of Clematis, Lonicera, Cotoneaster, and Spiraea, as well as Cydonia oblonga (Quince), Ribes sanguinium, and Rosa rugosa.
  • nigra: refers to the dark brown or black bark
  • Oregon State Univ. campus: southeast of Magruder Hall (Vet. Med.)
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  • plant habit

    plant habit

  • leaves


  • leaf


  • leaflets


  • leaf, comparison

    leaf, comparison

  • leaf, comparison

    leaf, comparison

  • male catkins, flowers

    male catkins, flowers

  • female flowers

    female flowers

  • developing fruit

    developing fruit

  • leaves and fruit

    leaves and fruit

  • plant habit, fall

    plant habit, fall

  • leaves and fruit, fall

    leaves and fruit, fall

  • fruit, fall

    fruit, fall

  • fruit and nut, fall

    fruit and nut, fall

  • plant habit, winter

    plant habit, winter

  • trunk, bark

    trunk, bark

  • winter twigs and buds

    winter twigs and buds