Stuff made.
While some specialists manage to grow regular crops by magical means, the Taaldarax does not wish to be dependent on people that may have unexpected happenings. Many crops are Saprophytic Plants and heterotrophs. These are plants that do not need to photosynthesize, but draw their energy from organic matter and are typically parasitic; many fields are laid in mushrooms first for this. Below list is based on real world plants, which is far from a complete list, but some examples; there are as many as 3,000 known real world species that fit the description.
Allotropa virgata, "sugar stick". Le-duh. Think about that one.
Hemitomes congestum, "gnome plant" - flowering plants that grow musky, cheesy smelling berries.
Monotropa hypopitys, aka yellow bird's-nest. - Flavoring, poisons and medicinal: A berry-bearing plant related to many common store berries. The stems produce oil similar to that of the wintergreens, which can be easily converted into methyl salicylate, used in minty flavoring, sweets and chewing gum. Lethal in large doses. The oil has also been used for intermittent fevers and is used to disguise the taste of other medicines.
M. uniflora, aka Fairy smoke, Eyebright - Medicinal use and filtration: Actually harvested in the filtering stations as they require a strange variety of elements to grow that is typically generated by local fungus. Treatment for sore or inflamed eyes (whence the name 'Eyebright'), application for warts and bunions, to ameliorate general aches and pains. Treatment for chorea, a nervous condition characterized by irregular, jerking movements. Physicians at one time administered a tonic that was used as a general sedative for any nervous or restless condition. In magical uses, The flowers are metaphor to a 'spotless sisterhood' engaged in their 'shy devotions near the singing brook' whose 'heads are bent, as if in prayerful mood." Whether considered foul or fait, Monotropa uniflora ranks as one of the true wonders of the forest world.
Pityopus californicus, California pinefoot. It produces a berry under a centimeter wide containing many seeds. The mature plant has a scent reminiscent of Brie cheese which is mirrored in the fruit.
Pleuricospora fimbriolata - It produces a fleshy berry under a centimeter wide.
Pterospora andromedea, aka giant bird's nest is a subfamily Monotropoidiae of the blueberry family. Their sticky output can be used to make glue.
Sarcodes sanguinea, snow plant. Medicinal use: Analgesic and soothing epithelial tissues. Treat ulcerated sores, irritated skin, and toothaches. A blood tonic, and a decoction has been used in this way. Dried and powdered this plant to relieve toothaches and other mouth pains.
Liverwort serves for both export under the belief it helps liver disease, as per the name, and also is a great aquatic plant used in modern aquariums to feed fish, thus being grown for underground fisheries.
Also broad variety of mushrooms. VERY broad. The mushrooms aren't even just for harvest, but also provide environment for these types of crops. Also... ferns, whisk fern, horsetails, and clubmosses, the tiny gametophytes of some species are saprophytic, living in association with fungi that aid in the uptake of water and nutrients.
In extra option as this ISN'T the real world, we could suggest chemosynthetic plants rather than just micro-organisms, and these are actually found in isolated cave water. It's also been hypothesized that chemosynthesis may support life below the surface of Mars, Europa, and others. At the bottom of the ocean, giant tube worms use chemosynthetic method to produce sugars and amino acids, as well as other things.
Many of these can, once their primary phase is over also be extracted for fatty oils, much the same way we get olive oil. Others make grand essential oils. The flowering ones may be used for unusual teas with medicinal effects, or even leaves alone. Others can be made into gums. These can create unusual resins much like frankincense and essentially make the area an incense factory. Many are particularly fleshy, and may be used for medicinal purposes, just like devil's claw. Others are heavy seed-bearing with medicinal properties, and some tuberous vegetables may be grown similarly to african potatos. They don't have any real incident of wood or bark.
Based on these, major unique exports would be: sugar-alternatives, unusual berries including even vegan cheese alternatives, medicinal exports, glues, resins and incenses.
This is not withstanding potential exports listed in other areas such as mass grains, phosphorus, and rare oils, or those inventions and trinkets made in the unusual conditions.
Exports are taxed at 40% with provisional deferral of profit to the masses as a whole, as stated elsewhere, in accordance to volume of work on average.