· An explanation grounded in the cited sources
Leaf
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Spruce needles
Needles provide an accessible starting point for exploring a spruce. Picea abies typically has four-sided needles about 1–2.5 cm long.
[3]Evidence for this statement
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Sources and versions
An explanation grounded in the cited sources
- Plant Ontology · 2026-01-09
2026-09-04 · CC-BY-4.0
Provenance and original
- Source version
- 2026-01-09 / f5e2a95d88fe08af22f49e522cc78481d990a0b0
- Arabidopsis thaliana basal leaf; photographed 14 April 2021
Retrieval date unknown · CC BY-SA 4.0
Provenance and original
- Original SHA-256
- 4c0da1e60a566728712e6443d8dfa11d4f4cd0084a0ef454d1262a3cdf05fa39
- Processing
- Resized and encoded as WebP; original 5 mm scale retained.
- Caudullo, Tinner & de Rigo · Picea abies in Europe · p.114
2026-09-06 · Reuse permission unverified
Provenance and original
- Source version
- 2016
- Arabidopsis thaliana Col-4, leaf 6, 19 days after initiation; Figure 2a, mature palisade mesophyll
Retrieval date unknown · CC BY 2.0
Provenance and original
- Original SHA-256
- 5510c5c1dba4162b182eed9ae054d2e97c25cc529740a5125ffcb1fd1c001b3c
- Processing
- Mature palisade panel extracted from Figure 2a; encoded as WebP. The shared scale bar is outside this panel and remains available in the full source figure.
Inspect structured data
- Content version
- 817942d8cceebffa841b0523d1af84bea630b3860691696cb8d50a9b4592051b
- Source version
- knowledge-20260909.1
- Updated
- 2026-09-09