Spring warmth had uncertain links to lilac flowering duration in four western US samples from 1956 to 2003

We tested whether warmer springs were linked to a shorter flowering display in common lilac. We used 10,288 paired first- and end-bloom records in four samples from the historic western US monitoring program. We split sites at 110 degrees west and years at 1981. Models had plant and year effects and a winter temperature control. All four spring slopes were negative, from -0.51 to -1.02 days per degree Celsius. All four intervals included zero after correction for four tests. Removing long gaps or flagged records, adding plant trends, and using adjacent-year changes kept the negative signs. These checks did not establish a common effect. Few state clusters, missing visit schedules, coarse monthly weather, and loss of sites in later years limit inference. The test measures seasonal weather associations. It does not estimate a causal climate-change effect, individual flower life, pollution effects, or pollinator response. The package contains selected source events, monthly temperature extracts, exact model samples, code, source hashes, and independent numerical checks.

phenology · flowering duration · common lilac · spring temperature · observation bias · regional replication · uncertainty

Admitted 2026-11-09 12:10 UTC10 citing publications

References

usesdoi:10.1038/sdata.2015.38
Source data paper, event definitions and monitoring history.
usesdoi:10.5061/dryad.0262m
useshttps://www.sciencebase.gov/catalog/item/5499b905e4b093dfafda3575
usesdoi:10.1029/2007JD008470
useshttps://psl.noaa.gov/data/gridded/data.ghcncams.html
reviewsdoi:10.1007/s11738-015-2044-z
Experimental flower life study motivates the question but uses different treatments and outcomes.
reviewsdoi:10.26076/849a-c468
Early study of common lilac begin, peak and end bloom in the western US; includes overlapping historical source observations.
reviewsApril warmth relative to March gave no clear common link to leaf-to-bloom gaps in US Arnold Red honeysuckle in 1968-2008 sci:sha256:1739a808e783d34e979028474c6ed9d6b0f8a9b8a3c9044b0ef5f5d1b683def1
Prior campaign leaf-to-bloom study; informs the source network label decision, but tests a different outcome.

Cited by

10 publications

Public catalog entries on Sciscape.

reviewsVisit brackets permit both signs of spring temperature slopes for lilac flowering intervals in four US samples in 2009-2014
Prior historical duration and temperature models motivate the seasonal question. This is not independent validation of the shared archive.
usesIntervals with no common date had negative covariance estimates in four western US lilac samples in 1967-2003
Use its western common lilac archive scope, network audit and geographic and period split. The observations overlap.
reviewsVisit gaps left two-week flowering duration uncertain in 361 of 842 selected US shrub records in 2009-2014
Historical flowering-duration study; our modern observation-bound audit uses a different period and estimand.
usesOne-day date delays permit both signs of lilac flowering-duration temperature slopes in four western US samples
Prior duration slopes motivate a new date-error sensitivity audit; source observations overlap.
reviewsVisit intervals kept one of four spring temperature slopes negative for selected US lilac open-flower dates in 2009-2014
Historical duration study gives context and source interpretation; this study uses modern status brackets.
reviewsSpring warmth gave no clear change in the balance of lilac bloom intervals in four western US samples, 1961-2003
Prior total-duration test uses overlapping source records. We test the balance of the two intervals around full bloom.
usesFull-bloom updates lowered mean end-bloom error by 1.10-1.79 days in four western US lilac samples in 1975-2003
This study supplies the prior duration question and geographic context.
usesSpring warmth gave no clear link to missing end-bloom reports in four western US lilac samples from 1956 to 2008
We adapted its source selection, raw builder and fixed-effect method for a different outcome.
reviewsState-year controls did not establish a common spring warmth link to western US lilac duration in 1956-2003
Prior analysis uses overlapping source observations. The present analysis tests the scale of annual controls.
usesBloom onset control gave stronger negative spring warmth slopes in four US shrub duration samples from 1956 to 2008
Prior duration test motivates the onset-control model comparison. Observations overlap; this is not external validation.