Azadirachta indica
Enable an agent to recognise Azadirachta indica, assess a particular neem tree or propagule, and select evidence-supported actions for its establishment, care, reproduction or harvest.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
Researched by: Codex + Grok
Purpose and description
Enable an agent to recognise Azadirachta indica, assess a particular neem tree or propagule, and select evidence-supported actions for its establishment, care, reproduction or harvest.
Azadirachta indica A. Juss. is a drought-tolerant, largely evergreen tree of the mahogany family (Meliaceae), native to the Indian subcontinent and now pantropical, whose imparipinnate leaves, bark and one-seeded drupes yield limonoid triterpenoids (notably azadirachtin) used as botanical insecticides, traditional South Asian medicines, and oilseed products.
It can be Identify or provisionally classify a suspected neem using complete leaves, reproductive material and an expert determination when necessary.; Assess a proposed planting position using local exposures and evidence appropriate to the plant's developmental stage.; Select a propagation approach, track its source material and verify germination or establishment.; Monitor crown change and investigate water stress, cold injury, pests or other competing explanations.; Plan and document fruit, seed or foliage collection while checking subsequent tree recovery and reproduction.; Trace biological samples into separate product assessments and evaluate observed recruitment before further planting..
Distinguishing features
Inspect a complete mature leaf: neem has once-pinnate leaves, whereas Melia azedarach typically has twice-pinnate leaves; distinguish a whole leaf from a detached leaf division. [NParks](https://www.nparks.gov.sg/florafaunaweb/flora/2/7/2738)
Compare mature leaflet margins: toothed margins support A. indica over the entire margins of A. excelsa; leaflet counts overlap and cannot decide identification alone. [NParks](https://www.nparks.gov.sg/florafaunaweb/flora/2/7/2738)
Check the leaflet combination of an asymmetric base, tapering tip and sometimes curved outline; require agreement with leaf architecture rather than accepting one feature. [NParks](https://www.nparks.gov.sg/florafaunaweb/flora/2/7/2738)
Where available, corroborate foliage with small pale flowers in branched clusters and oval fruits approximately 1-2 cm long; fruit colour alone is insufficient for identification. [NParks](https://www.nparks.gov.sg/florafaunaweb/flora/2/7/2738)
Scope
+ Identification of neem against similar Meliaceae, including incomplete or conflicting specimens.
+ Individual-tree origin, developmental stage, crown condition and reproductive state.
+ Site suitability and observed responses to water availability, drainage, light and cold.
+ Propagation provenance, seed handling and demonstrated establishment success.
+ Tree-level harvesting consequences and links from sampled tissues to measured composition.
+ Local recruitment and evidence needed before planting, retaining or removing neem.
- Manufacture, composition specifications and application instructions for neem oil, extracts and pesticides.
- Clinical treatment, medicinal efficacy and human or veterinary dosing.
- Complete soil, climate, irrigation-system and land-parcel models.
- Regional ecosystem dynamics and population-level invasion management.
- Timber-product grading, processing and commercial supply-chain operations.
Characteristics
- Identification confidence
- unexamined | provisional | corroborated | disputed Controls whether an observation can support neem-specific propagation or harvesting decisions.
- Observed leaf architecture
- once-pinnate | twice-pinnate | other | incomplete specimen Makes the principal comparison with Melia azedarach inspectable.
- Leaflet diagnostic observations
- margin: toothed | entire | unclear; base: asymmetric | symmetric | unclear Supports comparison with A. excelsa and identifies specimens needing expert review.
- Plant origin
- linked mother tree, seed lot, nursery accession or documented collection locality Preserves the connection between identity, propagation history and later performance.
- Developmental and reproductive state
- seed | seedling | juvenile | established vegetative tree | flowering | fruiting | senescent | dead; concurrent states allowed Prevents applying adult-tree expectations to seedlings or treating absent fruit as proof of poor health.
- Tree dimensions
- height and crown spread in m; stem diameter in cm at a recorded measurement height Supports growth tracking, shade assessment and decisions about access or pruning.
- Crown condition trajectory
- estimated leaf loss and branch dieback in %, with dated photographs and observation interval Separates a single sparse-crown observation from progressive decline.
- Root-zone water exposure
- soil moisture by stated method; standing-water duration in hours or days Tests water-stress explanations against actual exposure rather than a general drought-tolerance label.
- Cold exposure
- minimum temperature in °C and exposure duration in hours, paired with plant stage Supports local assessment of cold injury and establishment suitability.
- Seed-lot germination
- % germinated, tested seed count, test duration in days and stated test conditions Makes sowing decisions depend on the actual lot and its handling history.
- Sample-specific azadirachtin result
- mg/g with analyte identity, tissue, fresh or dry mass basis, method and detection limit; unmeasured allowed Prevents assigning a chemical concentration to every neem tree or transferring a seed result to leaves.
- Off-site recruitment evidence
- linked seedling observations with location, distance from planted trees and parentage confidence Supports a local spread assessment without assuming every nearby seedling came from the recorded tree.
Where this came from
wikidata · CC0 1.0
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 6 bundles · 11 layers · 18 findings · 28 questions.
Neem identity and origin Establish whether the organism is A. indica and what evidence connects it to its recorded origin.
A common name or nursery label cannot resolve confusion with related trees or establish the origin of propagation material.
Diagnostic identification
Evaluate a combination of leaf and reproductive observations.
Neem determination
Record supporting characters, contradictory observations and missing material before accepting the identification.
- Does a complete mature leaf support A. indica rather than Melia azedarach or A. excelsa? definition
- Which missing or conflicting characters require reproductive material, a voucher or specialist determination? boundary
Origin and continuity
Connect the observed plant to a source without treating trade names as biological proof.
Traceable neem origin
Keep source locality, mother-tree identity and nursery claims distinguishable from independently verified facts.
- Which collection, accession or nursery record connects this plant to its source? provenance
- Is a claimed cultivar or selected seed source documented, and which traits were actually verified? provenance
Neem site and condition Assess establishment conditions and interpret changes in the living tree.
Neem tolerates drought but is sensitive to waterlogging, so water exposure must be interpreted explicitly. [NParks](https://www.nparks.gov.sg/florafaunaweb/flora/2/7/2738)
Establishment exposures
Relate the particular plant's stage and rooting situation to measured site conditions.
Site fit evidence
Record drainage, water supply, light and cold exposure with local evidence for acceptable conditions.
- What drainage, soil-moisture, light and minimum-temperature observations describe this neem's actual rooting site? measurement
- What evidence supports planting or retaining a neem of this developmental stage under those conditions? action
Crown change and injury
Separate observed symptoms from their proposed causes.
Neem decline assessment
Use repeated observations to distinguish locally expected leaf change from persistent damage requiring investigation.
- How have leaf cover, shoot growth and branch dieback changed relative to this tree's previous seasonal observations? measurement
- What evidence distinguishes water stress, cold injury, pest damage and other explanations before treatment is selected? action
Neem reproduction and propagation Track reproductive opportunity and the conversion of identified material into established plants.
Reported flowering varies with location, and seed viability depends on storage history; calendar assumptions alone cannot establish readiness. [World Agroforestry](https://apps.worldagroforestry.org/treedb/AFTPDFS/Azadirachta_indica.pdf)
Flowering and fruit set
Record local reproductive timing and observed fruit development.
Local reproductive performance
Relate flowering and fruit set to nearby neem trees, flower visitors and concurrent conditions without assuming causation.
- When did this tree flower, set fruit and produce mature fruit, and how was each stage recognised? measurement
- Where fruit set is low, what observations support investigation of pollination, maturity or environmental stress? boundary
Propagule handling
Follow collection, storage and establishment of seeds or vegetative material.
Propagation readiness
Determine whether a particular lot remains suitable for the intended propagation method.
- What collection date, maturity assessment, processing and storage conditions are recorded for this neem material? provenance
- What germination or rooting test supports using, retesting or rejecting this lot? action
Neem harvest and material evidence Connect collection decisions to tree performance and traceable tissue observations.
Foliage harvesting can affect seed production, while reported chemical composition varies with source and handling. [World Agroforestry](https://apps.worldagroforestry.org/treedb/AFTPDFS/Azadirachta_indica.pdf)
Harvest and regrowth
Assess collection or pruning against the purpose and observed recovery of the tree.
Harvest response
Record the organ removed, amount, timing and subsequent crown or reproductive response.
- Is this neem managed primarily for shade, seed, foliage or another documented purpose, and what competing harvest demands exist? definition
- What removal intensity and follow-up observations justify repeating, reducing or stopping harvest? action
Tissue-to-product boundary
Preserve the biological origin and limits of evidence accompanying collected material.
Sample-specific composition
Attach analytical results to the sampled organ and lot; require a separate assessment for any resulting product or proposed use.
- Which tree, organ, maturity stage and handling history does an azadirachtin measurement represent? provenance
- Which proposed efficacy or safety conclusions exceed the tissue measurements and must be assessed in a product or treatment model? boundary
Neem recruitment and local decisions Determine whether reproduction is producing unmanaged plants and what that means for local action.
Neem fruits can be dispersed by birds and bats, making recruitment beyond a planting relevant to tree management. [World Agroforestry](https://apps.worldagroforestry.org/treedb/AFTPDFS/Azadirachta_indica.pdf)
Recruitment observations
Locate and identify volunteer plants while preserving uncertainty about their source.
Unmanaged neem recruitment
Distinguish identified recruits from look-alikes and observed spread from assumed parentage.
- Where are confirmed or suspected neem recruits appearing relative to planted trees and maintained boundaries? measurement
- What evidence distinguishes seed-derived recruits, vegetative shoots and unrelated seedlings? definition
Local management basis
Link biological observations to the applicable site objectives and external requirements.
Plant, retain or remove
Make local planting and removal decisions reviewable without assigning a universal invasive or protected status to neem.
- Which current local authority records establish any planting restrictions, protection or required controls for neem at this site? provenance
- Given observed recruitment and the site's objectives, should the agent recommend planting, monitoring, fruit collection or removal, and what evidence supports that choice? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Kinds and varieties
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Indian neem (A. indica A. Juss. in the strict South Asian sense, the usual cultivated and wild tree)
- Siamese or Thai neem (treated as A. indica var. siamensis Valeton or as A. siamensis; the sadao of mainland Southeast Asia)
- High-azadirachtin versus ordinary seed provenances (selected Indian and later African plantings grown for insecticide manufacture)
- Cold-pressed neem seed oil (food/cosmetic and pesticide feedstock)
- Clarified hydrophobic extract of neem oil (a US pesticide active-ingredient class distinct from azadirachtin technical)
- Azadirachtin technical concentrates and emulsifiable-concentrate insecticides
- Neem cake (de-oiled kernel residue used as manure and nematode suppressant)
- Ayurvedic crude-drug parts: leaf (nimbapatra), stem bark, seed and expressed oil (nimba)
- Which of these kinds and varieties hold for the sense of Azadirachta indica this model covers, and on what evidence? provenance
Identifiers and schemes
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Wikidata - Q234584 - Item for the species Azadirachta indica.
- NCBI Taxonomy - 49082 - Taxid for Azadirachta indica; parent genus Azadirachta is 49081.
- IPNI / POWO - urn:lsid:ipni.org:names:578178-1 - Nomenclatural identifier for Azadirachta indica A. Juss. (1830).
- Binomial (botanical) - Azadirachta indica A. Juss. - The name that should be preferred over vernacular neem, nim, or Indian lilac in a registry.
- CAS Registry Number - 11141-17-6 - Azadirachtin, the principal insecticidal constituent of seed kernels, not the tree itself.
- US EPA pesticide chemical code - 121701 (azadirachtin); 025006 (cold-pressed neem oil) - Product-regulatory identifiers for the two main neem-derived pesticide actives in the United States.
- Which of these identifiers and schemes hold for the sense of Azadirachta indica this model covers, and on what evidence? provenance
Standards and regulation
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- US EPA under FIFRA: azadirachtin (PC 121701) and cold-pressed neem oil registered as biochemical/biopesticide actives, with separate labels from conventional insecticides.
- EU Regulation (EC) No 1107/2009: azadirachtin assessed and authorised as a plant-protection active substance; national product authorisations follow.
- USDA National Organic Program: neem and azadirachtin appear on the National List as allowed botanical pest-control substances, subject to label and formulation limits.
- Ayurvedic Pharmacopoeia of India (Ministry of AYUSH): Nimba monograph covering leaf, bark, seed and oil as official crude drugs.
- Government of India, Department of Fertilizers: mandatory neem-coating of urea (policy from 2015), which created a large industrial demand for neem oil and cake.
- FAO/WHO Joint Meeting on Pesticide Residues (JMPR) and national MRL schedules: residue evaluation of azadirachtin where the active is registered on food crops.
- Which of these standards and regulation hold for the sense of Azadirachta indica this model covers, and on what evidence? provenance
Real-world use
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Botanical insecticide and antifeedant in organic and low-residue horticulture (whiteflies, leafminers, some Lepidoptera and stored-product pests), usually as an emulsifiable spray rather than as raw leaves.
- Neem-coated urea and neem cake in Indian field agriculture as a slow-release nitrogen practice and as a soil amendment with some nematode-suppressing effect.
- Ayurvedic and Unani medicines, tooth sticks (datun), soaps, toothpastes and cosmetic oils; internal use is traditional but is not a modern pharmaceutical standard of care.
- Rural agroforestry: shade, windbreak and fuelwood plantings across India, the Sahel and parts of the Caribbean and northern Australia, often as a municipal street or compound tree.
- Seed-crushing industry: kernels pressed for oil, with the residual cake sold as manure; azadirachtin is then extracted from oil or cake for technical insecticide manufacture.
- Which of these real-world use hold for the sense of Azadirachta indica this model covers, and on what evidence? provenance
Typical measurements
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Mature tree height - 12-20 (occasionally to about 30) - m
- Azadirachtin in dried seed kernels - 2-6 (reported extremes roughly 1-9) - g/kg
- Oil content of kernel - 40-50 - % m/m
- Oil yield on whole fruit/seed as traded - 20-30 - % m/m
- Drupe length - 14-28 - mm
- Mean annual rainfall of successful plantings - 400-1200 - mm
- Which of these typical measurements hold for the sense of Azadirachta indica this model covers, and on what evidence? provenance
Failure modes and hazards
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Azadirachtin is photolabile: field residues collapse in hours to a few days in sunlight, so poorly timed sprays fail even when the product is genuine.
- Stored kernels and crude oil readily grow Aspergillus and can carry aflatoxins if drying and storage are poor.
- Seed is short-lived; untreated seed loses germinability in weeks to a few months, so nurseries fail when seed is held like orthodox crop seed.
- Some oil and soap formulations are phytotoxic (leaf burn) especially under heat, and azadirachtin is toxic to many aquatic invertebrates and to fish at spray-drift concentrations.
- Internal medicinal use in pregnancy is treated as unsafe in modern toxicology (abortifacient reputation of seed oil); overfeeding cake to livestock has caused poisoning.
- Adulteration and substitution of traded 'neem oil' (other vegetable oils, or Melia products) make both pesticide strength and food/cosmetic safety unpredictable.
- Contact dermatitis and respiratory irritation occur in processors and in a minority of spray operators.
- Which of these failure modes and hazards hold for the sense of Azadirachta indica this model covers, and on what evidence? provenance
Regional variation
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- India and Nepal: primary vernacular is neem/nim/nimba; the tree is a cultivated, sacred and industrial species, and neem-coated urea is a national fertiliser practice.
- Mainland Southeast Asia: Thai sadao is often Siamese neem (var. siamensis / A. siamensis), eaten as a bitter vegetable as well as used medicinally; it is not interchangeable with Indian insecticide provenances without checking azadirachtin.
- West Africa and the Sahel: twentieth-century introductions are now village and roadside trees; local use is mainly shade, malaria-related leaf decoctions, and soap, with much less seed-crushing industry than in India.
- Caribbean, Florida and northern Australia: planted and naturalised; in parts of Queensland and some islands it is treated as a weedy or unwanted exotic rather than as a crop.
- European and North American markets usually meet the plant only as an imported oil, cake or labelled biopesticide, not as a grown tree.
- Which of these regional variation hold for the sense of Azadirachta indica this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Melia azedarach (chinaberry, Persian lilac, white cedar) - Chinaberry has lilac (not cream-white) flowers and a yellow, globose, several-seeded drupe; neem has an olive-shaped, usually one-seeded drupe. Chinaberry leaflets are more deeply toothed. The two are not chemically equivalent: chinaberry fruits are more toxic to mammals and are not a legal substitute for neem pesticide oil.
- Azadirachta excelsa (sentang) - A larger Southeast Asian timber tree with a different leaflet suite and much weaker azadirachtin chemistry; timber and plantation identity, not insecticide identity, separate it from A. indica.
- Azadirachta siamensis / A. indica var. siamensis (Thai neem, sadao) - Treated as a distinct taxon or variety; leaves are used as a vegetable in Thailand. Confirm by origin, morphology (often broader leaflets, different inflorescence) and by assay if the intended use is azadirachtin yield.
- Moringa oleifera (drumstick tree) - Often planted in the same dry-land compounds. Moringa has twice-pinnate leaves and long dehiscent pods; neem has once-pinnate leaves and small fleshy drupes. No shared insecticidal limonoid profile.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of Azadirachta indica this model covers, and on what evidence? provenance
Sources
- Neem: A Tree for Solving Global Problems - Botany, native and introduced range, oil and cake uses, azadirachtin as the principal insecticidal limonoid, agroforestry and public-health uses, and limits of the 1990s evidence base.
- The Neem Tree: Azadirachta indica A. Juss. and Other Meliaceous Plants - Specialist compilation on taxonomy relative to Melia and Azadirachta excelsa, chemistry of seed limonoids, insecticidal modes of action, and formulation behaviour including photolability of azadirachtin.
- Azadirachta indica A.Juss. - Accepted scientific name, family Meliaceae, nomenclatural citation of A. Jussieu, and the Kew treatment of native versus introduced distribution.
- Azadirachta indica (Q234584) - Stable item identifier and crosswalks to taxonomic databases used as the registry-style name for the species.
- Azadirachtin and cold-pressed neem oil biopesticide registration documents (PC codes 121701 and 025006) - US distinction between azadirachtin technical and cold-pressed or hydrophobic neem-oil actives, labelled crop and pest uses, and the main regulatory toxicology file for formulated products.
What the second pass must settle
- Which current taxonomic treatment and diagnostic key should govern identification of atypical, juvenile or cultivated material, especially comparisons with A. excelsa?
- What locally validated limits for cold, waterlogging and drought apply separately to neem seedlings, container plants and established trees?
- Which seed handling and storage protocols preserve viability for the relevant provenance, and what testing interval supports reliable sowing decisions?
- What locally demonstrated harvest intensities preserve crown recovery and seed production, and how representative are available tissue-composition measurements?
- What recruitment impacts, native or introduced status, and current management requirements are established for the intended jurisdiction?