Definition
Fructus naturales (Latin: "natural fruits") are the natural products of land or animals that arise solely from the forces of nature, without human cultivation or labor. The category includes the fruit of trees, the young of animals, milk, wool, and metals produced from land. The concept originates in Roman and civil law and is used in property law to classify what a thing yields naturally, as distinguished from products that arise through human industry.
The term operates in property law primarily to determine ownership and rights when land or animals are transferred, leased, or otherwise subject to competing claims. As a general principle, fructus naturales belong to the owner of the thing that produces them. When that ownership is in dispute or subject to a transaction, the classification of a product as fructus naturales—rather than fructus industriales—determines which party is entitled to it.
Common Confusion
FRUCTUS NATURALES vs. FRUCTUS INDUSTRIALES. These two categories are the primary division of fruits in civil law property analysis and are frequently encountered together. Fructus industriales ("industrial fruits") are products of land that result from human labor and cultivation—annual crops such as grain, vegetables, and other plantings that require sowing, tending, and harvest. Fructus naturales, by contrast, arise without human effort. The distinction matters because fructus industriales are often treated as personal property (emblements) even while attached to the land, giving a tenant or cultivator rights to harvest them after a tenancy ends. Fructus naturales do not carry this special entitlement. Confusion arises because some products—orchard fruit, for example—can appear to straddle the line; courts have generally treated orchard fruit as fructus naturales because the tree itself grows by natural process, though the orchard was planted. The Burrill entry and the maxim frumenta quae sata sunt solo cedere intelliguntur (grain which is sown is understood to form part of the soil) illustrate that even attached grain was treated as part of the realty until severed, a rule that reflects the fructus industriales side of the divide.
Why It Matters in Research
Researchers working in 19th-century American property law or in materials derived from civil law systems (Louisiana, Quebec, and to a degree the early common law) will encounter this term frequently in disputes over landlord-tenant rights, life estates, usufructs, and sales of land. The critical research trap is assuming uniform treatment across jurisdictions: common law systems absorbed the fructus naturales/fructus industriales distinction but did not always apply it identically to the civil law sources from which Black's and Burrill draw.
In usufruct contexts—heavily documented in Louisiana law—the usufructuary's rights extend to fructus naturales, and the timing of severance determines which party in a succession or sale is entitled to the product. Researchers examining conveyance disputes must check whether the jurisdiction follows the civil law rule (ownership of fruits passes with ownership of the producing thing) or a modified common law rule tied to severance.
The term also surfaces in secured transactions and agricultural lending history, where classification of livestock young, wool, and milk as fructus naturales affected whether a creditor's lien on the parent animal extended to its natural products.
When reading older American treatises and digests, note that the Latin is often left untranslated with only a passing gloss. Mackeldey's Civil Law (cited by Burrill as 1 Mackeld. Civ. Law, 156, 154) is a primary civil law source for these definitions and is available in English translation; researchers needing the doctrinal foundation should consult it directly rather than relying solely on dictionary summaries.
Historical Dictionary Support
Black's and Burrill agree on the core definition—products arising solely from the powers of nature—and both list substantially the same examples: fruit of trees, young and milk and wool of animals. Black's adds metals, which Burrill does not mention in this entry but which follows from the civil law treatment of natural mineral yields.
Burrill is the more useful entry for research purposes. His citation to Mackeldey places the definition squarely in the systematic civil law tradition, and his citation to Calvinus's Lexicon (Calv. Lex.) connects to the learned law lexicography that shaped how American lawyers of the 19th century understood Roman-derived property concepts. Black's entry is briefer and less sourced, though accurate.
Neither dictionary provides meaningful discussion of how American courts applied the distinction in common law jurisdictions, which is precisely where the research difficulty lies. Both entries reflect the civil law baseline without mapping its reception into equity or common law property doctrine. Researchers should treat both entries as starting points for the doctrinal concept, not as descriptions of uniform American practice.
Jurisdictional Note
The fructus naturales/fructus industriales distinction has its strongest statutory and doctrinal presence in Louisiana, which follows the civil law tradition and codifies the concept in the law of usufruct. In common law states, the distinction appears primarily in equity, landlord-tenant law, and older property treatises, with less consistency in judicial application. Researchers working outside Louisiana should verify whether a given court adopted the civil law classification or reasoned from common law emblements doctrine instead.