Artocarpus altilis (Parkinson) Fosberg

Tree up to 35(-40) m tall, with buttresses, evergreen or deciduous. Leafy twigs 5-22 mm thick, minutely whitish appressedly puberulous to subglabrous, often also brown (to yellowish) (sub)hirsute or setose (to strigose), drying brown to blackish; lenticels concentrated in the upper part of the internodes or ± scattered, few or numerous. Leaves spirally arranged; lamina coriaceous to chartaceous, elliptic to subrhombic to obovate in outline, 20-80(-100) by 15-50(-60) cm, mostly pinnatifid with 1-5(-9, occasionally-20) pairs of lateral lobes or segments, the incisions mostly to halfway, occasionally down to near the midrib, base cuneate to rounded (to subcordate), apex short-acuminate to acute, margin subentire to repand (to coarsely dentate), ± revolute; upper surface whitish to brownish (appressedly) puberulous to hirtellous or to subhispidulous, also brown set(ul)ose to strig(ill)ose on the main veins (or subglabrous), smooth to scabridulous; lower surface whitish to brownish appressedly puberulous (or to subhirtellous) on the veins, the hairs straight, on the smaller veins the hairs patent and all or some uncinate, all hairs on the smaller veins minute and appressed, or on the main veins also brown set(ul)ose, strig(ill)ose, or subhirsute, scabridulous to smooth; lateral veins 9-13(-18) pairs, (in entire laminas) some or most branched or forked away from the margin, tertiary venation scalariform, ± prominent; petiole 3-9(-13) cm long, 3-7(-10) mm thick, whitish to brownish appressedly puberulous, often also brown (sub)hirsute or set(ul)ose (or strigillose); stipules (3-)10-25(-35) cm long, whitish to brownish appressedly puberulous, often also brownish (sub)strigillose to (sub)hirsute or setose (to strigose), or brownish to yellowish subsericeous to subvillous or hirsute, caducous. Staminate inflorescences axillary, solitary; peduncle 1-6 cm long, whitish to brownish appressedly puberulous to substrigillose or to hirtellous, or also brown (sub)hirsute or setulose (to strigose), ± scabrous to smooth; head cylindrical to clavate to spicate, 5-30(-40) by (0.5-)1-3(-5.5) cm; perianth tubular, 1-2 mm long, the apex 2-lobed, subhispidulous or subglabrous; stamen 1.5-2.8 mm long, anther 0.6-0.8 mm long; interfloral bracts absent (or present and peltate). Pistillate inflorescences axillary, solitary; peduncle 2-14 cm long, whitish strigillose and also brown setulose or brown to yellowish hirtellous to (sub)hirsute, ± scabrous to smooth; head obovoid, ellipsoid, subglobose, or cylindrical; perianth tubular, c. 1 mm long, whitish to brownish (retrorsely) hispidulous to puberulous (or subglabrous), the apex 2-lobed to convex; stigma bifid or simple; interfloral bracts usually absent, sometimes present, and then often as rod-shaped processes. Infructescences ellipsoid to subglobose to obovoid or to cylindrical, 5-10(-15) by 5-10 cm or 15-30 by 10-30 cm diam., covered by 2-3 mm long pyramidate, 2-8 mm long cylindrical, or 8-15 mm long subulate to filiform, often ± curved apices of the perianths, sometimes intermixed with 0.5-2 cm long subulate to filiform, often ± curved processes, rarely with peltate bracts; fruits ellipsoid, 1-1.2 or 2-2.5 cm long.

A tropical plant. It occurs in the hot, humid, tropical lowlands. The plant is purely tropical and normally below about 65
 altitude, but trees grow from sea level up to about 1150 m. Seeded types are more dominant in the west of Papua New Guinea. Trees are killed by temperatures below 5°C. It probably requires an average temperature over 22°C to grow well. It tends to grow in the temperature range 16°C to 38°C. It grows on a range of soils providing they are well drained. There is some cultivar difference in drought tolerance and salt tolerance. Uniformly warm humid climates suit it best. An annual rainfall of 200-250 cm and a relative humidity of 70-80% suits. It suits hardiness zone 11-12.

The large seeds are roasted and eaten. The flesh of the fruit is eaten cooked. It can be boiled, baked, steamed, mashed, or turned into soups, puddings, cakes and pies. Dried fruit are made into flour. The young leaves are edible. The male and female flowers are edible.

Seeded forms are self sown by birds or bats, and also grown from seed. The presence or absence of seeds significantly affects the production. Seeded trees are mostly propagated by seed which needs to be sown fresh, without seed drying out. Seedless trees are propagated by root cuttings. Cuttings of roots 1.5 cm to 4 cm across and 25 cm long are suitable. Cuttings can be rooted during the wet season, in sand. They should be placed horizontally. They need to be kept moist and shaded. Using intermittent mist improves root formation and cutting establishment. Rooting hormones also assists. This process takes 10 weeks or more and then rooted cuttings should be hardened off in a sunny position for up to 3 more months before planting out into the field. Young plants do best with adequate sun and not shade. Root suckers produced naturally, or by damaging the roots, are a common method of production of new material. Marcottage or budding can also be used for propagation. The vegetatively propagated trees are therefore clones and the variation is presumably therefore somatic. Fruit set can be improved by dusting male flowers onto female flowers 3 days after they emerge. Because trees often occur from natural seed dispersal by fruit bats and marsupials trees are often randomly spaced and common in secondary forest. A spacing of 10-1
 is suitable between trees. Fruit can be 12-22 cm long and 9-17 cm wide. The fruit shape varies from round to oblong. Leaves vary from entire to deeply lobed and from rough to smooth and shiny. The central core and the skin are not eaten. Seeded fruit have projecting tuberances on the surface of the fruit. Seedless fruit have rounded or 5 to 6 sided processes on the surface. Male and female flowers grow separately on the same tree. Male flowers form an oblong catkin while female flowers form a globular head. The flowers are in the axils of leaves. Both flowers normally appear at the same time. Artificial pollination has resulted in increased yields in some places. This is both an increase in fruit size and more fruit retained on the tree to maturity. The pollen in the male flower is available 10 to 15 days after emergence. It is about 3 months from flowering to fruit maturity. Seeded fruit have 30 to 90 seeds per fruit. Trees rarely receive much attention after establishment but pruning of branches to allow easier access to fruit is sometimes undertaken. Seedless fruit are picked before maturity when the fruit is eaten by boiling. Harvesting mature fruit can be sweeter fruit but they need to be cooked by baking or roasting. Seeded fruit are normally allowed to drop and are then harvested. Seeds are boiled in salted water or roasted. A mature tree can yield up to 700 fruit per year. The seeds are about 20 % of dry matter as protein with a good nutritional balance. The essential amino acid levels are high for vegetable protein. Fresh fruit are highly perishable and need to be handled carefully and efficiently. Pit preservation of breadfruit involves lactic acid fermentation. The fermentation needs to be undergone for 2 to 3 months to produce a palatable product. Breadfruit slices can be stored under refrigeration in a fresh marketable state at 14°C for up to 10 days. Segments can be boiled for 2 to 5 minutes then frozen at minus 15°C for at least 11 weeks.