Seed supply and breeding targets for Scots pine and Norway spruce in Sweden

Seed supply and breeding targets for Scots pine and Norway spruce in Sweden Dag Lindgren at workshop Delineation of Breeding Zones Hann Munden, March 23, 2009 http://www-genfys.slu.se/staff/dagl/TREEBREEDEX/

Levels of “targets” • An existing seed source (seed orchard) gets a delineated permitted or recommended area, but comparison with other seed sources makes the delineation less fixed. • Delineated areas are needed for estimates of needed seed orchards. • For long term breeding, “targets” are needed rather than zones. • For seed orchard composition, recruitment area around the main target.

Sweden is extremely simple! Sweden extends at northern latitudes, where latitude (light climate) is more important. Warming is welcome in Sweden! Precipitation is rather uniform, drastic slopes and mountain forestry uncommon. For choice of seed source, sites are characterized with: heat sum and latitude. • Heat sum can be adjusted for e.g. exposure (or climate change) • Latitude is more critical at more northern latitudes (thus Sweden) • Latitude = light climate • For other factors, the consideration is species.

Existing seed sourceVästerhus seed orchard Photo: Anders Fries

Plantation with Västerhus seedlings Photo Dag Lindgren

Permitted seed sourcerather wide ranges

Västerhus permitted (enforced by the Forest Authority

A program (Planter’s guide by “Skogforsk”) exists assisting decisions • It is based on results from provenance trials • It can compare different seed sources at a given location for relative performance • It draws recommended areas for seed orchards

Scots pine seed orchard performance at different plantation latitudes, alt =200m, max=100, with Planter’s guide

Levels of “targets” • An existing seed source (seed orchard) gets a delineated permitted or recommended area. • Delineated areas are needed for estimates of needed seed orchards. • For long term breeding, “targets” are needed rather than zones. • For seed orchard composition, recruitment area around the main target.

Areas for estimatesfor current dimensioning of Swedish seed orchards (each color an orchard supply area) Pine Spruce

When seed orchards are mature, seed need have changed, recommendations will have changed, seed production projections has changed etc. Nothing is forever. • The major uncertainty is projecting species need, not provenance need.

Tree Breeding targets • Swedish long term tree breeding is structured in subpopulations, each with 50 tested founders. • The populations are targeted based on heat sum and light climate (altitude and latitude). • Figures show the targets of 24 pine (left) and 22 spruce (right) subpopulations “Map” of Sweden

Range of origins = v = 3 latitudes, but considering pollen, range of halfsibfamilies =v/2 = 1.5 latitude Plust tree origins Seed orchard location

A seed orchard recruits clones from several breeding populations! Recruitment area for the clones at Västerhus “Map” of Sweden

Inoptimality loss as function of zone size and origin range at the same latitude according to a model I made • Conclusions: • Zone size ranging over 2-3 latitudes for a seed orchard is OK • Avoid larger range of origin for clones than 3 latitudes in seed orchards

Global warming and zones in Sweden Dag Lindgren at workshop Delineation of Breeding Zones Hann Munden, March 24, 2009 http://www-genfys.slu.se/staff/dagl/TREEBREEDEX/

Environmental change How has Swedish tree breeding prepared for an uncertain future? • Structuring of long term breeding • Increased use of seed orchards • Seed orchards which produce robust and flexible seed

Sea level To prepare for an uncertain future, breeding effort are spread towards sea level and timber limit more than optimal today! Timber limit

Breeding materials are tested over a range of environments around the target environment! They will be more plastic and stable than Evolution made them!Evolution knows only now and here!!!!Tree breeders can do better than that!

Seed orchards produce seeds for variable conditions!! • Seed orchards are predictable and reproducible. • Clones selected from a wide range of stands and tested on several different sites. • A sufficient number of clones (17-25). • Some flexibility for immediate changes (roguing and selective harvest).

Global warming is here!!! • Now we are certain climate is warming!! • Immediate action is justified! • But as predictions vary very wildly, the uncertainty is larger than before!! • Prepare for a more uncertain future! • Response: wider range of testing!

Response to widened uncertainty!Breeding materials are tested over a wider range of environments!

Global warming is here!!! • Climate is warming!! • Immediate response justified! • Better guide lines will be formulated, till then react now, logic, simple and moderate! • Most certain change is temperature rise, other predictions are speculative and more difficult to manage.

How to mimic temperature change? • Pretend to change the elevation! • Logic. Physics says that air cools when lifted! And observations say that it is colder at high altitudes! • Temperature in Swedish vegetation period rises around 0.6 degree when elevation is reduced 100 m! • Thus, reduce elevation from 1990 to the actual year • Thus 3.33 meter/annually, 100 m in 33 years! • Or change heat sum correspondingly, but this is less transparent. • Equivalent to keeping the heatsum constant at a geographic location!

Response to warming:Move the map of Sweden!To keep to heat sum and latitude, the altitude of the breeding population target raises “Map” of Sweden “Map” of Sweden

Suitable climatic conditions Modified from Gösta Eriksson Forest genetics

How large temperature change? • Do something immediatly! • Do not overreact! Minimize reaction! Do not react so no change becomes a disaster! There are still scientists doubting it will be warmer 2040 than it was 1990, the harm if they are right should be limited! • Attention on first five years after plantation! Establishment important! • Few scenarios predict less than 2 degrees rise in a century. • Standard temperature period 1961-1990, it is most logic and simple to start from that! • Our experience on transfers is mainly based on before 1990 events. • A continuous change from 1990 to 2040, one degree in half a century. • Make it simple!

First, I looked at the Swedish temp to 2001, “Dag’s extrapolation” looks very reasonable Red arrow = ”Dag’s extrapolation” for Swedish global warming

When I found the Swedish temp to 2007, “Dag’s extrapolation” looks unreasonable modest…… Red arrow = ”Dag’s extrapolation” for ”Swedish” global warming

Two time horisons • Planting a seed source (about 2013) – 83 m altitude change. Includes planting of tests of the long term breeding population. • Planning seed orchards (planting about 2038) – 167 m altitude change • Sweden covers larger altitude differences than 150 m, the change seems rather safe.

Scots pine seed orchard performance at different plantation latitudes, alt =200m, 1990, with Planter’s guide 2023, Planter’s guide alt 100 m

Comments • Not much is lost if clima does not become warmer. • If clima becomes warmer than predicted, the losses will be reduced. • It is an immediate strategy, while thinking on a long term strategy. • A bit conservative, but psychologically better that next change plans for a hotter future than to admit overreaction. • For other changes than average temperature, the response is more in species than seed source.

Seed supply and breeding targets for Scots pine and Norway spruce in Sweden