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Introduction

Wood properties of sawn timber of Norway spruce ( Picea abies (L.) Karst.) grown under wide spacing Franka Brüchert, Florian Frisch, Udo H. Sauter IUFRO All Division 5 Conference, Taipei. Introduction.

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Introduction

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  1. Wood properties of sawn timber of Norway spruce (Picea abies (L.) Karst.) grown under wide spacing Franka Brüchert, Florian Frisch, Udo H. Sauter IUFRO All Division 5 Conference, Taipei

  2. Introduction “ If we regard future-crop trees rather as tamed solitaries than as partially unshackled captives, then science must also more intensly address research on solitary trees.“ABETZ 1987

  3. isolation at age ~ 15 years alternative A 350 / ha age 28-29 alternative B 700 / ha age 27-29 alternative FA 1600 / ha age 42 2 trees per site Silvicultural alternatives

  4. stem disc at 1.30 m stem disc at5 m 4 m log, split to 2x2m 2 short logs (1.37 – 2.06 m) 78 laths3 x 6 cm² 44 cants5 x 10 cm² Test material

  5. Results “Roundwood“

  6. Roundwood quality down-grading reasons: knots, ring width, compression wood

  7. threshold between grade B and C Branchiness of roundwood alternative A & B: ca. 80% sound knotsalternative FA : 7.5% sound knots

  8. Ring width of roundwood threshold between grade B & C threshold S 7/ S 10 threshold between A & B

  9. Results “Sawn timber“

  10. 26,7 30 22,6 17,8 20 thickest branch [mm] mean diameter of 10 0 A B FA alternative Knot dimension of sawn timber threshold S 10/ S 7 : wide side: 40mm narrow side: 20mm threshold S 13/ S 10: wide side: 20mm narrow side: 10mm

  11. S 0 = reject Knottiness of sawn timber

  12. 8 7,2 7,2 6 3,7 4 ring width [mm] 2 0 A B FA alternative Ring width of sawn timber (cants) treshold between S10 & S7 threshold between S13 & S10

  13. S 0 = reject Ring width of sawn timber

  14. Twist of sawn timber S 0 = reject

  15. Wood density, MOE & MOR of sawn timber

  16. Quality trend for future? branches ringwidth density juvenile core ??

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