The Tree Seed Centre is a registered facility for supply of source identified and tested seed for exotic and indigenous tree seed. The Seed Centre is there to provide advisory services to its clients which include:
• Seed handling
• Germination techniques
• Seed pre-treatment and methods of breaking seed dormancy
• We help our clients in selection of suitable species for the areas they intend to plant trees.
The tree improvement in Zimbabwe has been ongoing for more than 40 years and is in recognized as being amongst the best in the world. Over the past 22years a new multiple population breeding strategy has been evolved and stabilized. The tree improvement programme is geared towards the genetic improvement of tree species (mainly pines and eucalypts) in all aspects pertaining to their end use, including poles, sawn timber, pulp and afforestation. For example: to date, a minimum 17% gain in volume has been achieved in the first generation selections, cumulative 38% in the second generation and cumulative of up to 45% is predicted in the third generation selections over the original wild material of Pinus patula, and rotational age of sawn timber has been reduced from 30 to 25 years.
Seed collections, therefore, from all our pines species and most of our eucalypt specie are from genetically improved trees. Seed of other exotic and indigenous species comes from either selected trees or wild populations. The price list is therefore, columnised by category of seed available and a definition of each category is given hereunder. Our export trade in seed extends to countries like USA, South Africa, Mozambique, Indonesia, Australia, Swaziland and countries in the South and Central America.
Definition of seed categories
Collections made in plantations, smaller stands, shelter-belts, etc. and in the case of indigenous species, wild populations where no special selection criteria have been applied. As the name implies, it is ordinary, run-of-the-mill seed with some provenance details and an indication of the number of trees from which the seed was collected.
Seed collected from better than average or selected plus trees, which includes collections made from remaining trees in good stands and plantations that have been progressively, silvilculturally thinned leaving only the best components of the original stands. Information on origin and genetic base may be limited except in the case of indigenous species where numbers of parent trees and their proximity to each other may be recorded.
3. Genetically Improved Seed
Genetically superior seed of Pines and eucalypts is produced from an array of clonal and seedling seed orchards established from outstanding individuals of the breeding programme. The improvement programme itself, comprise of multiple diversified populations of bred species. The different populations are currently being bred at different levels of intensity (i.e. a function of breeding method and mating design) namely simple, intermediate and intensive. These three levels of breeding intensity provide seed categorized also in three groups namely, GG1, GG2 and GG3. GG3 is the most genetically superior category.
Seed is produced in multiple population tree breeding programmes from clonal orchards within sub-populations established and managed at different levels of breeding intensity, depending on the importance of species and the sub population within species may be created on the basis of environmental adaption, end use, provenance (natural or exotic) or genetic status. Three levels of breeding intensity are presently being applied within sub population and these are:
a. Simple level (GG1)
Seed for each generation is produced from mass selection in an undifferentiated sub-population. As a rule, large numbers of families are maintained in the populations to avoid inherent dangers of rapid reductions in genetic variability and consequent inbreeding.
b. Intermediate level (GG2)
Half-sib family identities are retained and seed of each generation is produced by a combination of between family phenotypic selections.
c. Intensive level (GG3)
Seed for successive generations is by controlled pollination between the best phenotypes selected in the genotypically proven half-sib families, and there is full pedigree control.
4. Family Identified Seed
It may be possible to supply seed in any category with half-sib and, more rarely, full-sib family identities maintained. This may help the grower to identify the best performers for use in making future commercial purchases of seed from the Forest Research Center. Seed supplied in this form is limited in the case of some species and is therefore, subject to availability and to special quotations of price.
Most seed orchard seed is bulked for sale. Although the genetic composition of the seed producers is controlled, the quantity of the seed from each tree or clone may vary with the individual depending on its prolificacy. Nevertheless, an attempt is alw3ays made to ensure representation of a range of genotypes within the sub-population.
All seed in stock is tested for purity, 1000 seed weight, and germination capacity. This is done periodically and the information is used in estimating the number of germinables per given mass of seed.
Effective Germination Factor (EGF)
All commercial seed is sold by “effective mass” which is based on the Effective Germination Factor (EGF). This factor is determined by calculating amount of seed required in every seedlot to yield the average number of germinable seedlings for that species, using the germination %, purity %, seed/gram and standard number of germination per species as variables.
An average number of germinables per gram (to the nearest 1000) has been established for the various species grown under local conditions, and these have been derived from records of test results conducted for over 25 years.
In practice, few seedlots yield the exact number of standard germinables per gram and adjustments have to be made using the EGF of the seedlot used in the sale. This adjustment converts actual mass to effective mass, to yield the standard number of germinables. Cost is, therefore, directly related to germination.
The only exception to sales based on the EGF will be when there is insufficient information to establish the average number of germinables seeds per gram for a particular species. In this case, seed will be sold on an actual mass basis, by setting the EGF at 1.0 (most indigenous trees fall under this category).
It must be stressed that the figures pertaining to the number of germinables per gram are those obtained under optimum laboratory conditions. Seldom, if ever, are these germination results achieved in the nursery and, ultimately, the most important consideration is the plantable seedling recovery. As a general rule, these recoveries average 70% and 25% of the total number of germinables for pines and eucalypts respectively, while a 10% contingency for blanking is considered realistic. Buyers are requested to make these allowances when ordering seed.
Knowledge of the number of seeds per gram for a particular species may be helpful to the buyer in calculating the quantity of the seed required for a planting programme.
CONDITIONS OF SALE
All prices are expressed in US dollars and will be reviewed periodically. Notice of intended price increases will be given to clients in advance.
Prices include packaging and our own handling expenses but exclude postage, air freight charges, customs documentation and our forwarding agent’s handling fees.
Discounts may be offered on large orders. Discounts may be considered for all recognized establishments selling seed, and for bulk purchases.
N.B our seed prices are per kilo of ‘effective mass’, i.e. the buyer pays for the number of viable seeds that can be expected from a kilo instead of for the ‘actual’ kilo mass. This effective mass concept is based on the use of the Effective Germination Factor (EGF).
Other than seed for specific needs and replenishing stocks for resale, most seed orders are based on producing enough high quality seedlings from a calculated amount of seed needed to establish a given planting programme. In such cases, it is requested that the order be placed stating: species, category, area to be established and spacing, together with as much relevant site information as possible. The exact seed requirements can then be determined by the Seed Centre personnel who, by using all the relevant seed data at their disposal, can provide single or multiple seed lots to best advantage with minimum wastage.
Many buyers still prefer to order seed by actual mass and will continue to be supplied on this basis, provided that the buyer understands that he /she will be charged for the effective mass of the order. Seed with a good Effective Germination Factor will cost more, whereas seed with a poor EGF will cost less, and so the buyer ends up getting more or fewer seedlings than needed. An order for can also be used to place an order.
Availability cannot be guaranteed. Please check before making payment. Seed of species not shown on the price list may be or could be collected, and enquiries are invited.
All seed for export is packed in strong, polythene bags and sealed. These are then baled in hessian and sewn closed.
A phytosanitory certificate will be procured for all export consignments. Please note that an import permit or licence from the importing country’s authorities must be produced when we apply for a certificate. Therefore, on confirmation of order, the buyer should ensure that his /her import permit (or a fax copy thereof) is forwarded with this confirmation or as soon as possible thereafter.
A sales sheet giving details of the stock(s) used in the sale will accompany the seed consignment. Ecological details of the seed source can be supplied on request.
Dispatch of seed will be carried out in accordance with the buyer’s wishes. This may be Free on Board (FOB), Cost and Freight (C&F), Cost Insurance Freight (CIF) or by Airmail or by DHL courier. Please note that the ownership and responsibility passes to the purchaser once goods have been handed to the designated carrier.
Advance payment is required. Proforma invoices will be sent to customers on confirmation of order to assist them in effecting payment.
Seed orders will be dispatched only after full payment in US dollars is received.
Seed orders and enquiries should be sent to:
Forest Research Centre
P O Box HG 595
Telephone: 263-4-498816; 498824; 496878/9
Fax: 263-4-498881; 498086
Payment may be effected by Bank Draft made out to Forestry Commission, Zimbabwe and sent to us at the Forest Research Centre, or cabled to our bankers for crediting to Forestry Commission Account. Account details are provided on request for quote.
All bank charges will be borne by the purchaser. Our bankers are:
Standard Chartered Bank Ltd
Africa Unity Square Branch
All seed offered for sale is tested under controlled laboratory conditions. However, we give no warranty , expressed or implied, where storage, nursery malpractice or other factors beyond our control result in seedling recoveries being less than those projected from test data , and we will not in any way be held responsible the resulted crop.
These terms are accepted by the purchaser when an order is placed.
The two EGF formulae, which are applied to pines and eucalypts, are:
EGF (Pines) a
b x cx d x e
EGF (Eucs) a
e x f
a= the standard seedling recovery for the species
b= the number of seeds per kilogram in the seed lot
c= the purity percentage of the seed lot
d= the germination % of the seed lot
e= nursery recovery percentage of the seed lot (provisionally set at 70% for pines and 25% for Eucalypts)
f= the number of germinable seeds per kilogram in the seed lot (eucalypts only)
STANDARD SEEDLING RECOVERY PER KG:
Euc. Paniculata = 317,000 germinable seedlings
Euc. Grandis (Unselect Mtao) = 457,000 germinable seedlings
(GG2 Mukandi) = 585,000 germinable seedlings
Euc. Citriodora= 136,000 germinable seedlings
Euc. tereticornis = 297,000 germinable seedlings
Pinus patula = 97,000 germinable seedlings
Pinus elliotii = 22,000 germinable seedlings
Pinus taeda= 31,000 germinable seedlings
ALLOWANCES TO BE MADE ON SEED ORDERS:
Eucalypts: Add 75% for nursery losses and 10% for blanking
Pines: Add 30% for nursery losses and 10%n for blanking