SIFAT FISIKA DAN MEKANIKA KAYU JABON MERAH (Neolamarckia macrophylla) DARI TIGA FAMILI HASIL SELEKSI STABILITAS PERTUMBUHAN DI KEBUN BENIH PACITAN

Rizka Clarasintya Gustyaningtyas, Ir. Fanny Hidayati, S.Hut., M.Sc., Ph.D., IPM. ; Dr. Ir. Arif Nirsatmanto, S.Hut., M.Sc.

2025 | Skripsi | KEHUTANAN

Kebun Benih Semai Uji Keturunan (KBSUK F-1) jabon merah (Neolamarckia macrophylla) telah dibangun di Wonogiri, Jawa Tengah dan Pacitan, Jawa Timur. Informasi mengenai stabilitas pertumbuhan pada lokasi berbeda serta sifat kayunya perlu diketahui. Penelitian ini bertujuan mengetahui sifat fisika dan mekanika kayu jabon merah dari tiga famili terbaik (7, 66, dan 50) hasil seleksi stabilitas diameter antara kedua lokasi, hubungan diameter terhadap sifat kayu serta hubungan berat jenis terhadap parameter sifat kayu lainnya. 

Sampel berupa 9 pohon jabon merah berumur 11 tahun dari KBSUK-F1 Pacitan. Penelitian menggunakan rancangan acak lengkap dengan satu faktor yaitu nomor famili dengan tiga ulangan pohon. Pengujian sifat fisika dan mekanika kayu mengacu British standard 373 (1957).

Hasil penelitian menunjukkan bahwa famili tidak berpengaruh nyata pada hampir semua parameter pengujian sifat fisika dan mekanika kecuali pada penyusutan dimensi dari kondisi segar ke kering udara arah radial. Rata-rata nilai kadar air segar, kadar air kering udara, berat jenis segar, berat jenis kering udara, berat jenis kering tanur, penyusutan total pada arah longitudinal, arah radial dan arah tangensial,  rasio T/R penyusutan total,  keteguhan lengkung statis pada batas proporsi,  modulus of elasticity, modulus of rupture, keteguhan tekan sejajar serat, keteguhan tekan tegak lurus serat, dan kekerasan kayu berturut - turut adalah 90,97%, 16,93%, 0,323, 0,337, 0,358, 0,21%, 2,62%,  5,44%, 2,38, 220,09 kg/cm2, 55.479 kg/cm2, 468,16 kg/cm2, 274,69 kg/cm2, 82,54 kg/cm2 dan 248,20 kg/cm2. Uji korelasi menunjukkan apabila diameter memiliki nilai hubungan yang sedang dan berat jenis memiliki hubungan yang sedang hingga kuat terhadap beberapa sifat fisika dan mekanika kayu. 

Progeny Test Seed Orchard (KBSUK F-1) of red jabon (Neolamarckia macrophylla) has been established in Wonogiri, Jawa Tengah and Pacitan, Jawa Timur. Information on growth stability across sites and wood properties is essential for further selection. The study aims to evaluate the physical and mechanical properties of wood from the three best-performing families (7, 66 and 50) based on stable diameter growth across both sites. Additionally, it examined the relationships between tree diameter and wood properties, as well as between wood density and other physical and mechanical traits.

Samples consisted of nine 11-year-old trees from KBSUK F-1 Pacitan, using a completely randomized design with three replications per family. Testing followed British Standard 373 (1957).

Results showed that the family had no significant effect on most wood properties, except for radial shrinkage from green to air-dry condition. The average values for green moisture content, air-dry moisture content, basic density, air-dry density, oven-dry density, total shrinkage in the longitudinal, radial and tangential directions,  T/R ratio, static bending strength at the proportional limit,  modulus of elasticity, modulus of rupture, compressive strength parallel to the grain, compressive strength perpendicular to the grain, and wood hardness were 90,97%, 16,93%, 0,323, 0,337, 0,358, 0,21% ,2,62%, 5,44%, 2,38, 220,09 kg/cm2, 55.479 kg/cm2, 468,16 kg/cm2, 274,69 kg/cm2, 82,54 kg/cm2 and 248,20 kg/cm2. Correlation analysis indicated that diameter had a moderate relationship with several physical and mechanical properties of the wood and density had a moderate to strong relationship with several physical and mechanical properties of the wood.

Kata Kunci : Neolamarckia macrophylla, Famili, Stabilitas pertumbuhan, Sifat fisika, Sifat mekanika