NOVELTY - Interplanting selenium enriched Camellia oleifera tree comprises grading, planting, mining outer slope, creating ditch, separating into sink, cultivating, improving soil, planting seedling, backfilling, adding diluted fertilizer, applying nitrogen, carrying out artificial propagation, watering, awakening of insect, beginning of bud, spreading spraying/mist, topping, shaping, carrying out planting, applying nitrogen fertilizer, phosphorus and potassium and bio-organic fertilizer, planting Chinese milk vetch, cutting, burying, applying selenium-rich soil and fertilizer applicator.    USE - The method is useful for interplanting selenium enriched Camellia oleifera tree (claimed).    ADVANTAGE - The method: increases yield of Camellia oleifera tree; and improves farming and forest planting.    DETAILED DESCRIPTION - Interplanting selenium enriched Camellia oleifera tree comprises (i) grading stepwise into the hillside woodland, planting, mining outer slope using stone heap dam ridge, centrally creating a ditch, placing interval segment along the longitudinal direction, separating into sink, providing first, second-tier outlet and outer third water port with staggered interval type arrangement, connecting ditch top with water supply device, providing outer upper part of the dam ridge with cross-type arrangement water pipe, setting water pipe tube body interval with water sprinkle hole/nozzle, cultivating inside and outside of the ditch and improving soil using 1:1:0.4:0.2-1.2:1:0.8:0.4 mass ratio of dry soil of drained, dried for 3-6 months and for 2-3 times tilled soil of paddy field, peat soil, selenium mixture including 4 kg green manure, 0.8 kg lime, 4 kg livestock manure, 0.5 kg oil cake fertilizer and 5-10 g sodium selenite and loamy soil including straw, tree leaf and weed ash and woodland soil mixture in the ratio of 1:2-3, (ii) planting on the ground with 50-55cm deep excavation from March to April, planting seedling of 2-3 years old in the cavity, backfilling, planting after 20 days, adding diluted fertilizer containing 2% urea and 0.2% potassium chloride and basic fertilizer comprising 10 pts. wt. green manure, 2 pts. wt. lime, 15 pts. wt. poultry manure and 8 pts. wt. oil cake fertilizer, setting tree stump surrounding the annular groove in August, applying 100 g nitrogen, carrying out artificial propagation in Autumn, watering ditch with water level lower than the first cultivation surface height of 12-17cm and cultivating on the surface blanket layer of leaf, (iii) awakening of insect, beginning of bud in April-May, spreading spraying/mist daily night through blowhole/nozzle for 3-5 minutes, topping along at 100-110 cm height, shaping, retaining 5-7 main branches, carrying out planting for second time at the end of March, applying 500 g nitrogen fertilizer to root, setting tree stump surrounding the annular groove in October, applying 500 g phosphorus and potassium and 2 kg bio-organic fertilizer, planting Chinese milk vetch in Autumn, cutting, planting Chinese milk vetch for second time, burying, applying selenium-rich soil and fertilizer applicator (120-150 kg/acre) containing 6 kg green manure, 0.8 kg lime, 4.0 kg livestock manure, 3.5 kg oil cake fertilizer and 3-5g sodium selenite, (iv) awakening of insects, applying fertilizer (1 time) in March and April, spreading spraying/mist daily night through blowhole/nozzle for 3-5 minutes, harvesting in 3 to 4 times April- May for 3-4 times, cutting main branch into strip at a angle of 40-45 degrees , trimming top lateral branch (3.5 m), applying nitrogen fertilizer (800 g/plant) and 800 g phosphorus and potassium and 5 kg bio-organic fertilizer in October, carrying out fertilization during fruit enlargement stage, spraying organic selenium fertilizer, planting Chinese milk vetch in Autumn, cutting, planting Chinese milk vetch in Autumn for second time and burying. The preparation of livestock manure comprises crushing sorghum, wheat and soybean powder in a ratio of 6:3:1, mixing to obtain fermentation substrate, mixing with selenium yeast in the ratio of 1:5, adding water, fermenting at 28 degrees C for 70 days and mixing animal feed.